Terminal Ballistics of the March 19 Shooting of President Chen: the Impossible Damage Patterns the Newton Group Forward

Terminal Ballistics of the March 19 Shooting of President Chen: The Impossible Damage Patterns The Newton Group Forward

This article was written for those who are willing to invest the necessary time to absorb the details of the evidence in the March 19 shooting, and make an intellectual effort to understand the scientific argument presented herein, before making an objective appraisal of our conclusion. The only required scientific background is high school physics, plus a logical mind. For such a reader, we ask you to all questions about the shooter, the weapon, and the motif, and consider the central question we try to answer in this article: Is the totality of the damage pattern of the lead bullet found in Chen’s clothing reconstructible in a laboratory setting? We think the answer is “NO”. We will first recall the official evidence, the relevant scientific background. Then we will present the relevant scientific background, our analysis and results of our experiments, to explain why the damage pattern cannot be reconstructed. You, dear reader, are invited to judge whether our conclusion is correct. Please take your time to check the cited literature to make sure that we did no misrepresent the facts. You are also encouraged to repeat the experiments, that is if you have at your disposal enough time, patience and resources. We trust that, after many hours of hard work, you will be confident on your ability to make a fare judgment. You probably would have preferred having a certified impartial authority to make the judgment for you. Unfortunately such an impartial authority is difficult to find. We tried, but we were could not find an established forensic expert, who was willing to work pro bono, without help or blessing from Taiwanese authority, and look at all available evidence, including those the Taiwanese authority may find inconvenient, and pronounce a straight verdict. The forensic experts we talked to preferred to advise us that, it was not their job to estimate the probability that all surgeons who treated

1 President Chen made the same unlikely error about the burn mark and the depth of his wound, the probability that Chen’s undershirt happened to be defective, and the probability that a yet-undiscovered conﬁguration of Chen’s abdominal tissue and clothing will produce the same damage pattern. Those, they say, are the job of the persecutor, the judge, and the juror. They did not want to contemplate whether the March 19 shooting was staged, not openly at least. The principal of presumed innocence has worked very well for President Chen and the CIB. The Taiwanese police and the Criminal Investigation Bureau (CIB) have been doing their busy work, chasing the invisible shooter and the elusive “underground weapon factories”. They are satisﬁed with their version of the truth, based on selected evidence; those evidence that may incriminate Chen were conveniently ignored. This article is about those inconvenient evidence and the story they tell. Our hope is that, you, dear reader, thinks that truth matters, just as we do. We would like to ask you to make a deliberate judgment, about the truth of the March 19 shooting, and tell your friends about it. That will be your contribution to the march truth.

2 Introduction Taiwanese President Chen Shui-Bian was reported to be shot on March 19, 2004, a day before the presidential election. The event changed the dynamics of the campaign, propelling Chen to victory by a margin of 0.2%, despite being consistently 4–7% behind in the polls in the days and weeks before the election. There were gross violations of the standard security protocols before and after the shooting. The crime scene was not secured, and key evidence was lost or destroyed. CNN reported on March 23 that

“No arrests have been made, no weapons found and no suspect identiﬁed, . . . , leading to accusations about political interference in the investigation.”

That report remains an accurate description. The authority’s decision, three months later, to decorate General Chen Tsai-Fu, the President’s Chief Aide- de-Camp, who sat in the front seat of the jeep at the time of the shooting, and to give a commendation to General Shen Tsai-tien, the Vice Chief, on May 19, despite the serious dereliction of duty of both men, does not inspire confidence. We are a group of scientists working in diverse fields, brought together by the March 19 event, and united by the simple idea that truth matters. Our goal is to study the terminal ballistics of the lead bullet found in Chen’s clothing, and to determine whether the same damage pattern can possibly be reconstructed in one single shot, objectively and scientifically. The for- mative event of our group was an innocuous conversation between two us on March 21, about the damage pattern of Chen’s abdominal wound, presum- ably caused by the round-nosed lead bullet in Chen’s clothing. We thought it would be useful to know whether Chen’s abdominal damage, as officially announced, is compatible with the laws of nature. Moreover, this question can be settled by an experiment on terminal ballistics that is quite feasible. In subsequent weeks, we received help from many scientists, some joined our groups, others generously shared their insight and expertise. In two months, we had a working device in place. Preliminary testing not only confirmed our initial ideas about the wound pattern, but also led to unexpected discoveries about the damage to the clothing. Our collective effort over a period of more than five months proves, beyond a reasonable doubt, that

3 the March 19 shooting of President Chen was staged.

More precisely, the totality of the damage pattern, of Chen’s abdominal wound and his clothing, as announced by the authority, could not have been caused by the round-nosed lead bullet found in his clothing in one single shot.

Our conclusion is based purely on the oﬃcial evidence and the terminal ballistics of the lead bullet. Factors based on normal human behavior are not considered, nor are the factors in the interior and the exterior ballistics. The ignored factors include:

(a) the possible motif of the shooter,

(b) the number of shooters and the number of shots ﬁred,

(d) the type of ﬁrearm used,

(e) the propellent and primer used, and

(f) the shooting distance.

What we are saying is that, no matter what weapon and powder were used, where the shot was ﬁred from, how good a gunman the shooter was, or whether the shooter intended to kill, a lead bullet of the same size and shape as the one found in Chen’s clothing simply could not produce all the damage in Chen’s clothing and abdominal tissue as announced by the authority. Not in this world! The reasons leading to the above conclusion will be elaborated in later sections. We will focus on four distinct features of the damage pattern, each contained in the oﬃcial evidence1.

(A) the presence burn mark on the abdominal wound,

(B) the length (11 cm) and the depth (2 cm) of the graze wound,

1See §1 for a list of the oﬃcial evidence.

4 (C) the presence of an exit hole on the undershirt and the absence of any exit hole on the shirt, and

(D) the inconsistency of the entrance holes;

Among them, the presence of burn mark (A)is perhaps the most conspicuous. However it is an established fact that bullets do not burn the skin, despite the common misconception to the contrary. This well-documented fact has been known for more than a hundred years, and is a consensus among forensic experts. Here is a quick summary of the reasons. The surface temperature of the lead bullet was no higher than 200 at impact, and the contact time with the skin was less then 0.1 millisecond. The amount of heat transfered from the lead bullet to Chen’s skin in 0.1 millisecond was minuscule, impossible to cause any burn injury. Further discussion and scientiﬁc documentation of this fact will be presented in §3. The second feature (B) is a horizontal graze wound on the abdomen, 2 cm deep and 11 cm long. Such a graze wound simply could not have been caused by the lead bullet found in Chen’s clothing. That bullet is 1.01 cm long and 0.81 cm in diameter, and the abdominal surface is curved. We do not know of any documented case of a graze gunshot wound in the abdomen exceeding 9 cm, with a depth twice the length of the bullet, nor of any ballistic mechanism which has any chance of producing such a graze wound. The maximal size of graze wound were were able to produce on abdominal tissues of anesthetized animals were far below the 2 cm deep, 11 cm long combination. If any person says that a 2 cm deep, 11 cm long graze wound is possible, then please construct one2 on the abdominal tissue of any mammal you choose, with a lead bullet of the same shape as in the March 19 shooting, and tell us the impact parameters. The third feature is related to an unexpected discovery, that there is no way the lead bullet could have been stopped by the shirt on exit without penetrating it, after it perforated the undershirt. Contrary to intuition, although the bullet ﬁrst hit the undershirt on its exit path, the shirt should have been penetrated before the undershirt was. The reason is that undershirt is much more elastic than the shirt. A high speed camera at about 20,000 frames

2A two-hole perforation wound does not count, the depth of the wound has to be at least 180% of the length of the projectile, and the length of the graze wound has to be at least 9 cm.

5 per second, tells the following story about the penetration process. After the undershirt was hit by the round nosed lead bullet, it began to deform as the bullet moved forward and hit the shirt. The bullet, covered by the deformed undershirt, proceeded to perforate the shirt, pushing a part of the undershirt through the hole on the shirt, until the undershirt reached its elastic limit and was perforated. Afterwards the undershirt retraced its path through the hole on the shirt and went back to its original position. Sometimes, when the impact velocity is close to the threshold velocity, one found a nose-like deformation of the undershirt perched on the bullet hole on th shirt, with the bullet trapped inside the nose-like deformation. See §5 for more information. Returning to the feature (C), that there is no exit hole on Chen’s shirt, but there is an exit hole on Chen’s undershirt. This feature contradicts the ballistic property of the undershirt and the shirt explained above. Besides the simplest explanation, that the March 19 shooting was staged, the others we can think of are all unlikely scenarios, such as Chen’s undershirt was defective near the exit hole. The fourth feature, that the size and the shape of the entrance holes are inconsistent, consists of two parts: (a) The length of the entrance hole on the shirt, 2.4 cm long, is more than twice the length of the bullet, and also more than 1 cm longer than entrance holes on the jacket and the shirt.

(b) The impact angle of the bullet with the jacket is inconsistent with the impact angles with the shirt and the undershirt, implying an impossibly high angular velocity for yawing and tumbling. See §6 for details. In our experiment, the only situation, where a 2.4 cm long bullet hole can be produced on the shirt, was when the shirt fabric was placed in near-contact distance to the muzzle, so that the airflow from the muzzle made the bullet hole significantly bigger. Dr. Henry Lee, the noted forensic expert, made the point to one of us in June of 2004, that none in our group is a forensic scientist, consequently we do have a license to practice the profession of forensic science. That is certainly true from a legal point of view. Scientifically, however, it has no bearing whatsoever on the validity of our conclusion. We stand by our conclusion, that features (A)–(D) above cannot possibly be caused by the said round-nosed lead bullet in one shot. We think any qualified scientist

6 will agree. If a rational person is to take the position that the March 19 shooting of Chen was not staged, then that person will have little choice but to insist on all of the following:

(a) Chen’s attending physicians, including three experienced surgeons who treated the wound, all mistook congealed blood for burn marks or lied about it.

(b) The same physicians also made the wrong estimate on the depth of the graze wound by at least 200%, or all lied about it.

In addition, she or he still has to concoct a plausible scenario for the entrance holes, and reconstruct feature (D) in one shot. Is this position reasonable or even tenable? A cynic may say that the March 19 shooting has been thoroughly politi- cized, and the science of terminal ballistics is not socially or politically relevant, for many reasons:

(a) Most people are unable to understand the technicalities and nuances in a scientific report and make independent judgment, because they do not have the time, patience, or adequate scientific background. They already made up their mind about the truth of the Presidential shooting one way or another, and will not be swayed by a scientific report.

(b) There will never be a “deﬁnitive version” of the truth. The testimony of the witnesses, how the evidence was collected, the design of the experiments and the interpretation of the data can and will all be questioned.

(d) There is no chance that a sitting president can be unseated on the strength of a technical report, especially if nearly half of the voters view the shooting as a legitimate, if distasteful, campaign tactic.

The above points are well taken, but we disagree with the view that our entire eﬀort is a futile exercise and best forgotten.If the March 19 shooting

7 was staged, then it is a naked grabbing of power and a subversion of the democratic process. To tolerate or condone such an behavior violates the basic tenets of any democratic society. We are mindful that, by making the public accusation, we are exposing ourselves to ridicules and retaliation by the ruling Democratic Progressive Party, their propaganda machine, and the Taiwanese government they con- trol. Still, we believe that in a few years, the Taiwanese people will be able to confront the 3/19 shooting with dispassion and objectivity, and come to see it as what it really was: a serious criminal act committed by the highest level of the government. Before that day comes, let us remember what Emile´ Zola’s wrote in his famous article J’accuse for the Alfred Dreyfus case.3 “Ce néstpas, dáilleurs,que je désespèrele moins du monde du triomphe. Je le répèteavec une certitude plus véhémente: La véritéest en marche et rien ne l’arrêtera.. . . quand on enferme la véritésous terre, elle s’y amasse, elle y prend une force telle d’explosion, que, le jour oùelle éclate,elle fait tout sauter avec elle.” (As for myself, I have not despaired in the least, of the triumph of right. I repeat with the most vehement conviction: truth is on the march and nothing will stop it. . . . when truth is buried underground, it grows and it builds up so much force that the day it explodes it blasts everything with it.)

3Following Zola’s example, we accuse President Chen Shui-Bian for staging an assassi- nation and subverting the democratic process. We accuse Mr. Hou Youyi, Director of the Criminal Investigation Bureau, for releasing deceitful reports aimed at misleading the public, and for suppressing evidence that incriminates Chen. We accuse Ms. Cheng Xiaoguei, Chief of CIB’s Forensic Department, for conducting an experiment in which incriminating evidence were intentionally ignored. We also accuse Ms. Cheng for withholding information incriminating Chen, unless she can prove herself and the Forensic Department blissfully ignorant of basic facts about wound ballistics, that bullets do not burn the skin, and that a graze wound 2 cm deep and 11 cm long inﬂicted by a 1 cm long bullet is a pipe dream.

8 Terminology cartridge A cartridge normally consists of four different parts: the projectile, the propellent, the cartridge case, and the primer. bullet The projectile of a cartridge that leaves the muzzle of a firearm when it discharges. propellent The actual source of energy of a firearm that accelerates the bullet to a certain velocity. The “smokeless powder” has almost completely replaced black powder as a propellent. black powder The standard composition of the black powder is: 75% potassium nitrate (KNO3), 15% charcoal (C) 10% sulfur (S). smokeless powder Modern propellent for small firearms, either nitrocellu- lose powder (nc) or nitroglycerine powder (ngl). primer The primer is the chemical mix in the ignition system of a cartridge. terminal ballistics Terminal ballistics studies the penetration of the projectile into the target. wound ballistics Wound ballistics is a part of terminal ballistics, concern- ing the penetration and the effect of a projectile when the target consists of biological tissues. yaw The yaw, or degree of yaw, of a bullet is the deviation of the long axis of the bullet from its line of flight. tumbling Tumbling refers to the rotation of a bullet around a lateral axis through its center of mass; it is caused by the yawing moment.4 rifling The rifling of a gun barrel consists of the spiral grooves in the interior of the barrel, and the metal left between the grooves—the lands.A smoothbore barrel is one without rifling.

4The two English verbs “yaw” and “tumble” both are translated as “taumeln” in Ger- man and “tomnoyer” in French, in ballistics literature.

9 Convention on romanization of Chinese names When the official spelling in English (often following the Wade-Giles romanization systems) of a person’s name is known, we use the official spelling and spell the name with the pinyin system in parentheses. When we are unable to find the official spelling, the pinyin system will be used. The family name precedes the given name. For instance, Hou is the family name of Hou Youyi.

Preliminary remarks 1. A good reference for gunshot wounds is [DM]. Here is a quote from the retired Homicide Commander Vernon J. Geberth of N.Y.P.D.

“Without a doubt, this book is the most comprehensive text on gunshot wounds available today.”

2. A good reference for wound ballistics is [SK]. It contains a extensive literature on the all aspects of wound ballistics, including the morphological and chemical changes of biological tissues at impact. 3. Newton’s laws of motion implies the following basic principal of terminal ballistics. With the target and projectile fixed, the damage inflicted on th target depends only on the location of impact, the orientation of the projectile at impact, and the instantaneous velocity vector of the center of mass of the projectile at impact.5 Moreover, the damage depends continously on the impact parameters above. So small variations of the impact parameters will produce the same damage pattern. In experiments in impact engineering, projecting system powered by com- pressed air (gas guns) are often employed. Gas guns offer fine resolution of

5A more precise way to formulate the problem is to consider the slug as a rigid body, since the slug only deformed slightly in the trajectory. The group E(3) of rigid motions in a three-dimensional Euclidean space is a six-dimensional Lie group, which is a semi-direct product of the rotation group SO(3) with the group of translations R3. The movement of the slug is a curve in E(3). Newton’s law is an second order ordinary differential equation in the six-dimensional configuration space E(3). The initial condition for such a differential equation consists of a point q0 in E(3) and an element X0 of the Lie algebra of E(3). It is convenient to take q0 to be the unit element of E(3). The element X0 is an element in the six-dimensional vector space Lie(E(3)); three of the components of X0 accounts for the linear momentum of the center of mass, the other three parameters accounts for the angular momentum. However the effect of the angular momentum is quite small, therefore ignored.

10 the muzzle velocity, within 1 m/sec for the lead bullet found President Chen’s clothing. The pressure that can be eﬀectively applied to the said bullet above can reach 1,500 psi (= lb/in2), yielding a muzzle velocity close to 300 m/sec with a 1 meter long accelerating tube (barrel).

11 1 Hard evidence

In this section we summarize the oﬃcial evidence, with comments on the source and reliability of some of them.

1.1 Bullet (1) A round-nosed home-made lead bullet was found between the Presi- dent’s undershirt and his shirt.

(2) The diameter of the lead bullet is 8.1 mm; it weighs 3.88 g and is 10.09 mm long.

(3) No striation mark was found on the lead bullet. Therefore it was ﬁred from a smoothbore ﬁrearm.

(4) Blood trace was found on the bullet, matching the President’s blood sample in DNA testing.

(5) The bullet has retained its shape with minor deformation at its heel.6

(6) There are no obvious ﬁber marks on the lead bullet.

(7) White and blue“transferred fibers” were found on the lead bullet. The White fiber matches the jacket, and the blue fiber matches the shirt.

(8) Two cartridge cases were found a few hours after the incident.7 The inner diameter of the two cases are both 8.1 mm. No marks were found on the outer surface of either case. Black powder residues were detected inside the cases.

(9) Machine marks were ﬁnd on the home made lead bullet.

Remark Statements (1), (2), (4), (5), (8) were announced by the authority in the days after the shooting; See for instance the report by Xie Mingjun

6In answering a question from Legislator Chou on May 31, on whether the tool marks on the lead bullet has suﬀered any discernible deformation, the Criminal Investigation Bureau (CIB) said that “No obvious deformation was found on the lead bullet.” 7A resident in the neighborhood of the crime scene saw the two cases and reported them to the police. In press reports the neighbors said that the two cases were under a police vehicle, and was not noticed until the police car moved.

12 on page A6 of China Times, March 21, 2004. These data were reconfirmed in the Dr. Henry Lee’s news conference on April 11, 2004. For the statement (3) about the absence of striation marks, see page A8 of China Times on March 22, 2004, which cited statements by the police. Item (6) is in a written statement by the Criminal Investigation Bureau (CIB) in June of 2004, responding to a written question dated May 31, from Legislator Chou Hsi-Wei (Zhou Xiwei in pinyin), a member of the Legislative Yuan. The first sentence in (7) was announced in Dr. Lee’s news conference on April 11; see the Remark below. The second sentence of (7) is in the written statement of CIB mentioned above. Item (8) was announced by CIB on March 23; see page 4 of Chinatimes Express, March 23, 2004. It was reconfirmed in Dr. Lee’s news conference on April 11. Remark Dr. Henry Lee, an American forensic expert with international reputation, was invited by the Taiwanese authority to examine the evidence in the March 19 shooting. He visited Taiwan from April 9 to April 11, 2004. In a news conference on April 11, he explained what he and his forensic team had been able to confirm in their examination of the evidence, and what remains to be done. That news conference was reported in detail by all major new media in Taiwan; see for instance page 2 of Chinatimes Express, April 11, and page A6 of United Daily News, April 12. He emphasized that his job, as a forensic scientist, is to examine the evidence provided by the CIB; determining whether the March 19 shooting was staged is the job of the investigator, i.e. the CIB, and the prosecutors. He also pointed out that weapon identification and trajectory reconstruction were to be carried out by the CIB and not his team, citing his team’s lack of experiences about home- made firearms as the reason. His report was delivered to Mr. Lu Renfa, the Chief Prosecutor, on August 30, 2004. Remark Marks by tool bits can be clearly seen from the photograph of the lead bullet released in Dr. Lee’s news conference on April 11. The tool marks are not to be confused with striation marks, which are parallel marks on the bullet produced by the lands of a rifled barrel.

1.2 Clothing (1) Two holes were found in the President’s undershirt, corresponding to the two ends of the abdominal wound. (They are the entrance and exit holes.)

13 (2) Only one hole was found on the President’s shirt. Similarly there is only one hole on the jacket8. (They are the entrance holes.)

(3) There are black marks on the entrance hole on the jacket, shirt and undershirt, and also on the exit hole on the undershirt. Tests by the CIB lab detected lead residue in the three entrance holes and the exit hole on the undershirt. No powder residue was found on the clothing.

(4) The entrance hole on the jacket has an irregular shape, about 1.4 cm long and 0.4 cm wide.

(5) The entrance hole on the shirt has an irregular shape, about 2.4 cm long and 0.5 cm wide.

(6) The entrance hole on the undershirt has an irregular shape, about 1.0 cm long and 0.6 cm wide.

(7) The exit hole on the undershirt has an irregular shape, about 1.1 cm long and 0.4 cm wide.

(8) The distance between the entrance hole and the exit hole on the undershirt is about 9 cm. 9

(9) There is an L-shaped damage on the lower left side on the shirt. (The entrance hole on the shirt is on the lower right side.) The longer (vertical) side is about 2.6 cm long; the shorter (horizontal) side is about 1.8 cm long.

(10) CIB agents examined the shirt with a microscope, and found no sign of penetration on the L-shaped damage on the shirt. In a written answer to a question from Legislator Chou, the CIB said that the L-shaped damage was not caused by the impact from the lead bullet. The CIB also that there is no way to determine the impact location after the bullet penetrated the undershirt on its exit path.

8We obtained more than a dozen of Chen-Lu campaign jackets worn by Chen on March 19. The bullet hole is on the right pocket. The jacket is lined by a layer of fabric. The bullet actually penetrated ﬁve layers of fabrics on the jacket. 9According to a report on page 2 of United Nightly News, June 24, 2004, the CIB said that the distance between the entrance and exit holes on the undershirt is 8 cm.

14 (11) There is no horizontal burn mark on the President’s undershirt, corresponding to the abdominal wound. Remark Statements (1), (2) and the first sentence of (3) were announced by CIB in a news conference on March 23; a diagram indicating which clothing was penetrated on entrance or exit was released during that news conference. See for instance page A5 of China Times, March 24, 2004. Items (4)–(10) is from a written statement by CIB , responding to a written question from Legislator Chou Hsi-Wei dated May 31, 2004. The existence of black marks in statement (3) was confirmed in Dr. Lee’s news conference on April 11, 2004. Remark The presence of lead residue in statement (3) is in the written statement from CIB mentioned above. The absence of gun powder residue in (3) was announced by CIB on March 23. The CIB forensic laboratory employed two methods in their test for powder residues: flameless atomic absorption spectrometry (FAAS) and scanning electron microscope-energy dispersive X-ray spectrometry (SEM-EDX)10; see the report by Wu Junling on page 4 of Chinatimes Express, March 23, 2004. A team of American forensic experts, consisting of Dr. Cyril Wecht, Major Timothy Palmbach, and Michael Haag, visited Taiwan from March 29 to March 30 to help the investigation. They examined Chen’s clothing, confirmed the absence of powder residue, and communicated the result to Dr. Henry Lee.

1.3 Wound (1) There is a horizontal linear symmetric11 grazing gunshot wound, along the President’s abdomen. It is 11 cm long, 2 cm wide and 1–2 cm deep, located about 3 cm below the navel. (2) There is a visible burn marks along the rims of the wound, according to the testimony of all physicians who attended and treated President Chen on March 19, including the three physicians who traveled with the President on March 19 and the three physicians of the Chi-Mei hospital who treated the President.12 10See [DM, chapter 12] for more information about FAAS and SEM-EDX 11The wound is both left/right symmetric and up/down symmetric, as one can see from the photograph released by the CIB on March 20. 12No signiﬁcant bruising or swelling around the wound were seen on the picture released to the public.

15 (3) Oﬃcial records at the Tainan Medical Examiner’s oﬃce show that there is a sewn-up wound on President Chen’s abdomen, about 9 cm long.

Remark The depth of the abdominal wound and the presence of burn marks on the wound cannot be veriﬁed by examining the wound after the healed wound, which had been cleaned and sewn together at Chi Mei Hospital. Moreover, it is diﬃcult to make any meaningful judgment from the few photographs of the wound released by the authority. Therefore one has to rely on testimony by the eyewitness, to be presented in the next section.

2 Eyewitness testimony about the wound

The presence of burn injury and burn mark on Chen’s abdominal wound was extensively reported in the first week after the shooting. This piece of evidence was hailed as “proof” that Chen’s wound was caused by gunshot, therefore not staged, in a concerted effort by Chen’s PR machine. For what- ever reason, the presence of burn mark does not seem to be included in the list of official evidence by the CIB, and it is not clear whether this piece of evidence was formally communicated to Dr. Lee’s team for consideration. We only know that burn mark was never mentioned by the CIB in any of their official announcements, nor was it presented in the news conference by Dr. Lee on April 11. Similarly, the depth of Chen’s abdominal wound, “about two centime- ters”, was extensively reported. Again this piece of information has never been mentioned by the CIB, nor in Dr. Lee’s April 11 news conference The presence of burn mark and the depth of the wound are the consensus of all known eyewitness of Chen’s abdominal wound before it was treated and sewn together. The known eyewitness include the three physicians who traveled with Chen on March 19, member’s of the President’s medical team, Dr. Xiao Ziyou, an otolaryngologist of National Taiwan University Hos- pital,

Dr. Jian Xionfe, a plastic surgeon of National Taiwan University Hos- pital,

Dr. Tan Guanghuan, deputy superintendent of Songshan Hospital in Taipei, an orthopedic surgeon,

16 six medical professionals of the Chi Mei Hospital, where Chen was treated,

Dr. Steven Chan (Zhan Qixian in pinyin), superintendent of Chi Mei Hospital,

Dr. Li Haoxian, deputy superintendent of Chi Mei Hospital, a noted surgeon,

Dr. Lin Hung-jung (Lin Hongrong in pinyin), head of the ER department,

Dr. Zhang Jinmin, head of the radiology department,

Ms. Xiao Suquiu, head nurse,

Ms. Li Meihuei, head nurse, and the official photographer of the Office of the President. Below are samples of what the doctors said in official news conferences within 24 hours after the shooting, as reported by major news media.

Dr. Steven Chan, March 19:

“There was burn injury of the skin at the rims of the Presi- dent’s wound. Antibiotics were given as a preventive measure ...”

See page 4 of Liberty Times, March 20.

Dr. Lin Hung-jung, March 19:

“The President received 32 stitches, . . . There were black burn marks on both sides of the wound.”

See page A1 of United Daily Times, March 20, reported by Guo Xi- ansheng. The exact words also appeared on page 1 of Liberty Times, March 31.

Dr. Li Hao-Xian, March 19:

“There was a sharp wound on President Chen’s abdomen, with burn marks on it.”

17 Reported by Zhang Rongxiang, Central News Agency, March 20.

Dr. Xiao Ziyou, March 19:

“I immediately went to the President’s car, and examined the President’s vital signs and also his wound. Our preliminary determination was that the wound did not reach the abdominal cavity. The epidermis felt charred.”

Liberty Times, March 20, reported by Xu Shaoxuan.

Chi Mei Medical Center and President Chen’s medical team, March 19:

“A horizontal lacerated wound was found about 3 cm below the navel. It was about 2 cm wide, 11 cm long, and 2 cm deep, reaching the subcutaneous tissues13 . . . The medical team14, appraised the abdominal wound, and determined that it was caused by the penetration by a foreign metal object, likely to be a bullet, which entered from the right and exited to the left, resulting in a graze wound with burn injury.”

See the report by Wan Hueixing, page A5 of China Times, March 20, 2004. The report on page 2 of Taiwan Daily News on March 20 provides the same information, worded diﬀerently.

Dr. Chan, March 19:

“After President Chen and Vice President Lu were admit- ted to the Emergency Room of Chi Mei Medical Center, the deputy superintendent Dr. Li and the President’s medical team examined the President’s vital signs, which was stable. There was a horizontal lacerated wound on the abdomen, close to the navel, which was about 11 cm long, 2 cm wide. The wound was about 2 cm deep, but did not reach the abdominal muscles. In other words, only the epidermis, dermis, and the subcutaneous tissue were damaged.”

Liberty Times reported that

13The third layer of the skin, below the epidermis and the dermis. 14including the physicians of Chi Mei Hospital

18 “The abdominal wound extended to the second layer of subcutaneous fat”

and went on to emphasize that it was a graze gunshot wound.

The most compelling evidence of the presence of burn injury on Chen’s abdominal wound is perhaps the collective testimony of Dr. Xiao, Dr. Jian, Dr. Tan, Dr. Li, Dr. Lin, Dr. Zhang and Ms. Xiao in the news program Dahua News of the cable TV station SETN15. Invited by the anchor Zheng Hongyi, they went live on a special program of Dahua News on March 26, 2004, with express authorization from President Chen. It was a de facto deposition. In that program, they reaﬃrmed what had been reported by the media about the President’s wound, including the depth and the length of the wound, and added many details not previously reported. The presence of burn injury was conﬁrmed by Dr. Jian, the plastic surgeon in the President’s medical team, who said:

“The wound was irregular, not a knife wound, and there are burn injuries at the rims, . . . , so was treated as a gunshot wound.

There were no objection or modification raised about the burn injury, nor about the depth and length of the wound during the entire program. The testimony of these medical professionals were reported by Zhang Chunyu of the government-run wire service Central News Agency on March 26. On September 2, 2004, Dr. Jian, Dr. Lin and eight others on the medical staff of Chi Mei hospital testified in court. According to a report by Wang Jiyiu and Zhang Xiaoyi of China Times on September 3, Dr. Lin said that

“The rim of the President’s wound was neither sharp nor smooth. It was charred black, and looked like having being grazed by gun powder.”

Dr. Lin was very ﬁrm about the burn marks he saw. There is no denying that the presence of burn marks is part of the oﬃcial evidence.

How reliable are the testimony of these doctors, who, as a group, were very consistent about their description of the wound. For the beneﬁt of President Chen and the Taiwanese authority, we should ﬁrst discard the possibility

15a subsidiary of SETTV

19 that the doctors willingly lied, in unison. If they did, then every evidence announced by the authority is suspect. Furthermore, it is hard to believe that the Chi Mei doctors all lied for no good reason. So let us agree that the doctors reported honestly and professionally. The length of the wound is not in dispute: we have all seen the pictures, and Chen’s abdomen was observed by many American forensic experts. The width of the length is not very important for forensic purposes: an abdominal wound such as Chen’s would widen, or “open up”, after the its formation, a natural physiological phenomenon. What about the depth of the wound? The doctors may not have measured the depth of the wound, but they all described the depth of the wound in anatomical terms: the wound went beyond the epidermis and the dermis, reaching into the subcutaneous tissue, the second layer of the subcutaneous fat to be precise. President Chen is known to have a substantial “tuna belly”. The doctors’ estimate of 2 cm depth seems very reasonable from the point of view of human anatomy. Could it be that all those doctors, five surgeons among them, were mistaken? Is it possible that they only something black, and thought it was a burn mark? Let us first consider what the black stuff may be. Can it be soot? Here are some background information. In general the bullet may carry soot on its surface, and deposit the soot on the target. Here is what one finds on page 119 of [DM] on bullet wipe:

Bullet holes of entrance in the skin may have a gray coloration to the abrasion ring. This gray rim around the entrance is very common, and more prominent, in clothing, where it is called “bullet wipe”. Bullet wipe consists principally of soot, deposited on the surface of the bullet as it moves down the barrel, which is rubbed oﬀ the bullet by the skin or clothing as it penetrates the body.

Let us also remember that there were seven layers16 of clothing before the lead bullet could reach the abdominal skin, and soot was wiped oﬀ from the bullet by each of them. Not much soot would still be on the bullet after it passed through seven layers of fabrics. Remember that Dr. Lin Hung-jung

16The bullet hit the right pocket of the jacket. The jacket was lined by a layer of fabric. The bullet penetrated ﬁve layers of fabrics on the jacket alone.

20 talked about black burn marks, and Dr. Xiao says that the epidermis had a charred feel. The doctors saw something black, not grey. What the doctors considered as black burn mark could not have come from the bullet wipe. What about the possibility that the black stuﬀ the doctors saw were congealed blood, not burn marks. It is agreed among forensic pathologists that emergency room physicians often misinterpret gunshot wounds. This point is discussed on pages 256–257 of [DM]. It is clear from loc. cit. that, although emergency room doctors do often err in interpreting the number of projectiles, and also in diﬀerentiating exits and entrances, they are not prone to mistaking congealed blood for burn marks. Members of our group consulted extensive with senior physicians in Taiwan. The consensus, as expressed by the deputy superintendent of a teaching hospital of a national university in southern Taiwan, is Taiwanese surgeons may not be familiar with gunshot wounds, but they are experienced with burn injury; the surgical lasers and electro-cautery systems routinely used in surgery give them intimate famil- iarity with coagulated or cauterized tissues. The surgeons recognize burn injuries from the characteristics of damaged tissues. Those surgeons who attended Chen’s wound were not inexperienced residents; they are very good at what they do. They treated the wound, touched and felt it, and we can be assured that they proceeded very carefully when treating the President. It is highly improbable that they could have all made the same elementary error, misidentifying congealed blood, or soot in bullet wipe for that matter, as burned tissues.

3 Bullets do not burn the skin

Burn injury is caused by heat transfer to tissues. There are three key factors that limit the amount of heat transfered to a target from a projectile: the surface temperature of the projectile, the contact time of the projectile with the target. We will discuss the range of possible temperature of the lead bullet and its contact time with Chen’s abdominal skin, and see why it is absolutely impassible that there could have been any burn injury.

3.1 Surface temperature of projectiles How hot could that lead bullet be at impact time? There is a trivial upper bound, that temperature of the bullet must be lower than the melting point

21 of lead17, 327.4 at 1 atm, because the recovered lead bullet did not deform badly. The actual surface temperature of the lead bullet at impact time is signiﬁcantly lower than this trivial bound.

Marty, Sigrist and Wyler conducted an experiment to measure the skin temperature at the entry wound with infrared thermography. They used human skin, including the subcutaneous tissue, excised from ca- davers, heated to 30. Handgun shots were ﬁred from a close range of 1 cm, the distance∼ between the muzzle and the skin. With .25, .32, .38-special and 9-mm caliber cartridge, the measured skin temperature at impact never exceeded 56; see [MSW]. Their thermographic examination of a 9-mm Lugar in ﬂight, at a muzzle velocity of approximately 350 m/sec,18 put the surface temperature at 147–152.

In [SK, p. 185], the authors pointed out that only the surface of the bullet is hot, while the core remains cold.

“The thermal conduction being a rather slow process and the projectile motion taking place within less than a second, the generation of heat is limited to the top layer of the projectile and thus the core remain unaﬀected.”

They also cited [LM] for a theoretical estimate of temperature increase on the surface of a bullet. The results, for the 7.62 51 mm NATO projectile19, are: 160 inside the barrel, and at most× 55 due to friction with the air. So the absolute maximum surface temperature of the said NATO projectile can reach, from a room temperature of 30, is about 245.

The lead bullet in March 19 shooting had a low impact velocity, because it was stopped by the shirt on its exit path. The CIB estimated the impact velocity (with the jacket) at about 180 m/sec, based on three valid shots

17The exact composition of the lead bullet in 3/19 shooting is not known. It is likely to have antimony in it; the commercially available lead alloy in Taiwan usually contains 4–6% antimony. Adding antimony to lead increases the stiﬀness of the alloy, but lowers the melting point and the heat capacity. 18CIB announced their shooting experiment, with three valid shots for the lead bullet, on June 2004. The estimated the muzzle velocity is about 180 m/sec. 19The 7.62 51 mm NATO projectiles are used for military riﬂes. It weighs 9.50 g, and has a muzzle× velocity of 830 m/sec

22 in a shooting experiment. A team lead by Mr. Chen Hu, a former Chief Engineer at a Taiwan weapon factory conducted an experiment, sponsored by the Nationalist Party. Their result, with 40 valid shots20, was announced on June 30, 2004. They put the estimated impact velocity (with the jacket) at 162 m/sec. Experiments by our group gives the range of possible impact velocity of the lead bullet with the jacket, with the shirt, with the undershirt, and with the abdomen respectively.21 Our data shows that impact velocity of the lead bullet with Chen’s jacket is certainly between 150 m/sec and 200 m/sec.

3.2 Contact time of a projectile with the skin A crucial factor that limits the amount of heat transferred from the lead bullet to the abdominal skin is the contact time of the bullet with the skin. At an impact velocity between 150 m/sec to 200 m/sec, the contact time of the bullet with the skin would be at most 0.2 millisecond (0.0002 sec) according to [MSW, p. 3]. That short a time is far from enough to cause burn injury! The fact that a heat source at 200 with contact time 0.2 ms cannot cause burn injury on human skin can be illustrated by a game that many of us have played and enjoyed. Move a finger across the flame of a burning candle, say at 50 cm/sec; the contact time of the finger would be about 0.02 sec, the temperature of the candle flame varies, but it is at least 300. Yet your finger will only feel a little warm at most.

3.3 Total amount of transferable heat on the projectile There is a third factor, not as important as the previous two, that limits the amount of heat that can transferred to the target by a projectile, namely the total heat content of the projectile. We give a rough estimate of it in

20Central News Agency, June 30, 2004. 21We used 10% ordnance gelatin as tissue simulant, covered with diﬀerent layers of fabrics, impacted at diﬀerent angles, to determine the range of possible impact velocities. Our lower bound comes from threshold velocity for penetrating the fabrics on entrance. Our upper bound comes from the requirement that the bullet does not penetrate the shirt on exit. The “range of possible impact velocity” is the range between the upper and lower bound.

23 the next two paragraphs. Assuming for simplicity that the outer layer of the lead bullet had a temperature of 220, with a mass which is 25% of its total mass, 3.88 g, while the rest of the bullet was assumed to be at room temperature, about 30. The heat capacity of lead is 129 J/kg. The surface temperature of the bullet must be significantly lower than the surface temperature of the 7.62 51 mm NATO projectile fired from a military rifle. It is safe to say that× the surface temperature of the lead bullet at impact time is not higher than 200 m/sec. Combining the above figures, the total amount of thermal energy carried by the lead bullet that can be transferred to the skin at normal body temperature, is about 5 calories, according to the law of conservation of energy. Notice that we assumed 100% efficiency in heat transfer; the real figure is lower. What can be achieved with 5 calories of heat? Well, it can raise the temperature of 1 teaspoon of water by 1. Such a small amount of heat, delivered by an inefficient cauterization instrument, the bullet, surely cannot cause burn injury, not to mention burn marks.

3.4 Bullets do not burn the skin: documentations Once one knows the surface temperature of the projectile, the contact time with the skin, and the total amount of thermal energy carried by a bullet, it becomes clear that the heat transferred to the skin from a projectile is never enough to cause burn injury. It is such an obvious fact and common knowledge for the experts, that they will spend at most a sentence or two on this subject in a technical paper, a paragraph or two in a monograph, for the beneﬁt of nonexperts. Fortunately some of the experts did mention this fact in their publications. Below are some excerpts; the interested readers are invited to ﬁnd more details in the comprehensive books [DM], [SK] and the papers cited in them.

pages 84–85 of [DM], where [MSW] and [L1] are cited:

“While bullets may easily attain a surface temperature of over 100 after leaving the muzzle, the contact time between the bullet and the skin is extremely short, insuﬃcient to cause

24 a burn.22. . . That bullets do not burn the skin has been know for some time.23 In the late nineteenth century, Von Beck conducted experiments24 to determine the amount of heat imparted to both lead bullets of large caliber and jacketed .30-caliber rifle bullets. . . . The missiles were handled by the fingers and never possessed sufficient heat to burn the skin.”

page 187 of [SK]:

“The temperature of a projectile, mentioned above, is not suﬃcient to cause burns at impact on the skin or during full penetration, as contact time is far bellow one millisecond.”

page 3 of [MSW]:

25 “At a V0 of 350 m/s, the contact time with the skin amounts to only∼ 0.1 ms, which means that the relevant con- ductive thermal processes between the projectile and the skin cannot take place.”

3.5 Firing does not sterilize a dirtied bullet The question “can a bullet burn the skin” never attracted much attention, because it served no practical purpose. However there was a question which the military in the nineteenth century waw very much interested in, because it is related to the cause of infection of gunshot wounds.

Is the heat of a bullet suﬃcient to kill bacteria on it, rendering it sterile?

The answer to that question is a resounding “NO”, despite many people in the nineteenth or even the early twentieth century, including military and medical professionals, thought the contrary.

22Here Di Maio cited data in [MSW] to illustrate the surface temperature of a bullet and contact time with the skin 23Since the publication of [L1] in 1895, 109 years ago. 24This experiment was cited by Lagarde in [L1]. 25muzzle velocity

25 The first person to answer this question was Lagarde, who applied anthrax spores, vegetative forms of anthrax, curare, and ricin to sterilized projectiles before firing them. The heat produced in the firing process were never enough to kill the germs; see [L1], [L2], [L3, pp. 131–132]. The same question was re-examined by other scientists later. The answer was always the same: a dirtied projectile invariably carries bacteria into the target. A nice summary of these experiments can be found in [SK, pp. 186–187]; see [JGP], [TD],[THLW], [WBSH]. Bacterium prodigiosum (= Serratia marcescens), which is sensitive to heat and has a short survival time in a laboratory, was used in the first three papers cited above; staphylococci aurei was used in the fourth. Generally, bacteria were found throughout the shooting channel, including the exit wound. The contact time of the projectile with the germs are much longer than the contact time with the skin, almost by two orders of magnitude, since the shooting distance in the experiments [JGP], [TD],[THLW], [WBSH] above were at least one meter. Yet the total amount of heat was not enough to kill all the heat sensitive microbe Serratia marcescens. Is there even a remote possibility that the lead bullet burned Chen’s abdominal skin? Clearly the answer is “NO”. It is ironic that, during the first week, the presence of burn mark on Chen’s abdomen was emphasized by Taiwanese government officials and Chen’s supporters as proof of Chen’s innocence. Their argument was that burn mark “proves” that Chen’s wound was indeed caused by gunshot, therefore the March 19 shooting was not staged. It turns out that their argument was based on imagination, not science. What science tells us is that, the burn mark on the found cannot possibly be caused by the bullet, therefore the March 19 shooting of Chen was staged!

3.6 Abrasion ring and powder tatooing We have presented the scientiﬁc reason and experts’ opinion in monographs and published papers to show that bullets do not burn the skin. Yet many people are under the impression that burn injury is common in gunshot wounds, caused by very hot bullets cauterizing tissues. The fact is that, scorching or burning occurs only in contact wound or near-contact wounds, caused by the ﬂame or hot air from the muzzle. In the following we collect

26 some quotes from [DM] and [A], and refer the readers to [DM, chapter 4] for more information.

In contact wounds and near contact wounds, the skin is seared by the hot gases of combustion, and blackened by the soot. See [DM, pp. 65–71].

In intermediate-range gunshot wounds, the muzzle was held suﬃciently close to the target body, so that the powder grains expelled from the muzzle produce “powder tatooing” of the skin. Powder tatoo marks are not “powder burns”, but rather are punctuated abrasions. See[DM, pp. 71–72]

The maximum range of powder tatooing from a .38-special revolver with 4-in. barrel is 105 cm. The maximum range of powder tatooing from a .22 revolver with 4-in. barrel is 45 cm. See [DM, pp. 138–139].

The term “powder burns” does not have a precise meaning. Some people use “powder burns” to signify powder tatooing. Some others use it to signify searing and blackening of the skin due to the hot gas that occur from combustion of the propellent. See [DM, p. 72].

“For most handguns, powder soot deposition does not occur if the distance between the muzzle and the target is more than 30 cm.” See [DM, p. 75]

page 393 of [A]:

“The products of the muzzle blast are responsible for the zone of charring and stippling (“soiling”), popularly mis- called “powder burns” . . . ”

“Most entrance wounds are surrounded by a reddish or reddish-brown zone of abraded skin, called the abrasion ring. This is a rim of ﬂattened, abraded epidermis, surrounding the entrance track. . . . The abrasion ring occurs when the bullet abraid, or “rub raw”, the edge of the hole as it indents and pierces the skin.” See [DM, pp. 63–64].

27 The abrasion ring is not due to the bullet’s rotational movement as it goes through the skin,26 nor is it due to the bullet burning the skin. See [DM, p. 84]. The lead bullet that hit Chen in the March 19 incident was, according to the CIB, not ﬁred from close distance, because no powder residue was detected on Chen’s clothing. See China Times, March 23, page A7, and Chinatimes Expresss, March 23, page 4. So we can be sure that there were no scorching by hot gas from the muzzle, and no powder tatooing either.

3.7 What the CIB did and did not say The CIB is the agency in charge of the investigation of the March 19 shooting. On March 23, taking what it called an“unprecedented” step, the CIB circulated its forensic report internally, and disclosed details of the report to the press; see Chinatimes Express, March 23, page A4. On June 24, the CIB announced the results of its shooting experiment, with three valid shots for the lead bullet. The CIB Director Hou Youyi said on March 27 that the CIB “welcomes scrutiny by the Taiwanese society, as well as the international community, as long as it is legally permitted,”; see China Times, March 23, page A7. Taking up the oﬀer from Director Hou, let us examine whether the CIB did its job competently and professionally in investigating an important piece of evidence, the presence of burn mark on the wound. An important question is, was the CIB aware of the fact that bullets never burn the skin? On March 23, the CIB announced test results about the black marks on the entrance holes of Chen’s clothes. “No powder residue was detected on the three entrance holes, on the jacket, the shirt and the undershirt. The black marks on the entrance holes were caused by burning, resulting from penetration by the high speed lead bullet.” See page A4 of Chinatimes Express, March 23, 2004. The last sentence above, that the black marks on the bullet holes was caused by the bullet which burned the fabrics, was clearly wrong. On [DM, 339–340], Di Maio explained the source of black marks around entrance holes on clothing:

26The twist length of a 5.56 45mm NATO bullet, ﬁred from a M-16A2, is 7 in. It is a very fast spinning bullet, and× it makes a complete rotation in 7 in. The twist length of a .357 Magnum revolver bullet is 18.75 in. See [SK, p. 354]

28 “Bullet wipe” is a gray to black rim around an entrance hole in clothing. It is seen around holes made by both lead and full metal-jacketed bullets. It is not, as some people contend, lead wiped oﬀ the bullet but is principally soot. Lubricant and small amount of metallic elements from the cartridge, cartridge case, and bullet may also be present in the bullet wipe.

The reason why bullets do not burn the skin also proves that bullets do not burn clothing: There is too little contact time, the surface temperature of bullet is at most 250, and the total amount of thermal energy carried by the bullet is very limited. We do not know whether the CIB possessed the knowledge that bullets do not burn the skin. We do know that, at least one of their forensic expert thought that bullets can burn the clothing, a basic error. There are two possible answers; neither will enhance CIB’s credibility. Suppose they did not know this well-documented fact, existing in the published literature for over a hundred years, that bullets do not burn the skin. That would make the CIB an incredibly incompetent agency.27 If the CIB did not even know such a basic fact about gunshot wounds, how can its investigation be trusted? You do not want a medical student just failed a basic competency test in anatomy to operate on you. The other possibility, that the CIB knew that bullets never burn the skin, yet it did and said nothing after Chen’s attending physicians all said that there were burn marks on Chen’s abdomen, insisted that Chen suffered a gunshot wound, and dismissed the possibility that the shooting was staged. That would be an appalling offense. For then the CIB suppressed incriminating information and deceived the Taiwanese public through its intentional inaction and criminal negligence. If the CIB did not communicate the presence of burn mark to the American forensic experts invited to help with the investigation, deliberately, then the CIB obstructed justice. We would also like to point out that the CIB does not have final say determining whether the testimony from Chen’s attending physicians was credible; that authority belongs to the courts.

27The CIB consistently took the position that they are professionals, and labeled their critics as laypersons with groundless suspicions.

29 3.8 Summary of this section Bullets do not burn the skin. This is an immutable scientific fact. The eyewitness testimony on the presence of burn marks on Chen’s abdominal wound, from all physicians who treated Chen, unanimous and detailed, are convincing and cannot be dismissed offhand. If one believes the doctors’ testimony, then one has to conclude that the March 19 shooting of Chen was staged. If one is to take the position that the March 19 shooting was not staged, then one has to insist that all five surgeons thought that they saw coagulated or cauterized tissue while there were only congealed blood, an improbable supposition.

4 Length and depth of the wound

The physicians who treated Chen’s on March 19 said that Chen’s abdominal wound was 11 cm long and 2 cm deep; the subcutaneous tissue were damaged, the damage extends to the second layer of subcutaneous fat. The picture released by the authority shows a wound shaped like an elongated ellipse. The CIB said that the Chen’s wound was a graze gunshot wound. Below is a deﬁnition of graze gunshot wound, from [DM, p. 96].

“A graze wound is one in which a bullet strikes the skin at a shallow angle, producing an elongated area of abrasion without actual perforation or tearing the skin. In a tangential wound, the injury extends through to the subcutaneous tissue. The skin is torn, or lacerated, by the bullet.”

The diﬀerence between the shape of a graze and a tangential wound can be clearly seen from photographs A, B on page 98 of [DM]. In a tangential wound, where the skin is torn, the rim of the wound “branches out”, which does not in any way resemble the contour of an ellipse. The rim of a graze wound, however, is elliptic in shape. According to the eyewitness of attending physicians, Chen’s abdominal wound extends through to the subcutaneous tissue, so it should be a tangential wound and not a graze wound. But the shape of Chen’s wound is not what a tangential wound should be. One cannot help wondering why Chen’s abdominal skin had such a propensity toward a graze wound.

30 Remember that the round nosed lead bullet found in Chen’s clothing was 1.01 cm long, 0.81 cm in diameter. The depth of the wound, 2 cm, is twice the whole length of the bullet, 2.5 times the diameter. We were unable to find any documented gunshot graze wound whose depth is twice the length of the projectile. Nor could we find any documented case of a abdominal graze wound, not a two-hole perforation, which is more than 10 cm long. Is a graze of such extraordinary dimension physically possible? The impact velocity of the bullet was no more than 200 m/s, far lower than the speed of sound, therefore the possible effect of shock waves can be ignored.28 Since the bullet only grazed the abdomen, at a moderate velocity, the effect of pressure wave can also be ignored. As we saw in §3, a very fast spinning NATO projectile, fired from an M16A2, makes a complete turn in 7 in. The yawing and tumbling angular velocity of the lead bullet is much slower than the spinning angular velocity of the NATO projectile. Hence the rotational motion of the bullet makes negligible contribution to the length and depth of the graze wound. We conclude that the abdominal wound was formed by the bullet pushing the skin tissue in its way, a familiar mechanical process. The inexplicable question is, how is it possible for a lead bullet, 1 cm long and 0.8 cm in diameter, produce a graze wound 2 cm deep, just by pushing the skin tissue in contact with it? The sheer length of the graze wound, 11 cm long, is another feature of the wound that cannot be reproduced in a laboratory setting. When a bullet grazes the abdomen, there is a normal component of the reaction force exerted on the bullet by the skin, which tends to push the bullet away from the abdomen. The bullet yaws and tumbles, which also tends to make the bullet move away from the abdomen. There is no external force pressing the bullet toward the skin in the normal direction. In addition, the abdomen has a curved surface, making it far more easier for a projectile to produce a two-hole penetration than an 11 cm long graze wound. In our experiments, with the abdominal area of rabbits or piglets under anesthesia as the target, we able to produce graze wound at most a few cm long, and the wound was always at most 0.5 cm deep. A graze wound 11 cm long and 2 cm deep is simply out of the range.

28The pathological and morphological eﬀect of shock waves on biological tissues are discussed in [SK, pp. 281–194].

31 The critics may say that we have not tried hard enough. If we make a ten thousand shot, or a million shots, or ten million shots, then somehow, in an unspeciﬁed situation, one may hit the jackpot and produce a graze wound, not a tangential one, 11 cm long, 2 cm deep, just like Chen’s wound. We reject such wishful thinking. If anyone says such a wound is possible, then please show us how to reconstruct on in a laboratory. Tell us your conﬁguration of the target, the impact velocity and impact angle, we will check that. Experiments can be repeated; they do not lie. How can one defend Chen? Well, there are ways to “explain away” the problem about the depth and the length of the wound, by attacking the evidence. One can argue that, perhaps the doctors were mistaken, that the wound was not 2 cm deep after all. Or, the wound was only 0.5 cm deep, but somehow, inexplicably, it became 2 cm deep because of Chen’s body movement, before he was examined in the emergency room. Such scenarios are “possible” but unlikely; see §8 for more discussions.

5 Pinocchio’s nose

We purchased dozens of the undershirt of the same brand and style, and obtained through an intermediary the same fabric of the shirt, directly from Chen’s tailor. The long sleeve undershirt Chen wore on March 19 is much more elastic and resilient than his custom-made shirt. Therefore if impacted by the same round-nosed bullet, the threshold velocity for the undershirt is considerably higher than the threshold velocity for the shirt. Consequently whenever the undershirt is penetrated, the shirt must also be penetrated. The oﬃcial evidence, that the undershirt was penetrated on exit, but the shirt was not, ﬂies on the face of this fact. Her is a short description of the setting of a part of our experiment, for reconstructing the damage pattern of the exit holes. A piece of the undershirt was placed 2 cm apart from a piece of the shirt. Recall that Chen’s abdominal wound was located 3 cm blow his navel and above his belt. So the exit hole on the undershirt was close to the belt. Although the shirt and the undershirt was not tightly stretched, they should not be too loose in the area near the bullet holes. The tensions of the fabrics used in our experiment were adjusted accordingly.

32 During our preliminary tests to determine the threshold velocity of the fabrics, we found that the damage pattern the official evidence we were trying to reconstruct were absent. Either the bullet penetrated both layers of fabric, or it did not penetrate either one. The same pattern persisted for a while, as we adjusted the impact velocity closer and closer to the threshold velocity. When the impact velocity was very close to the threshold velocity, about 1–2 m/s less than the threshold velocity to be precise, a third pattern appeared. The bullet did not penetrate the undershirt, the first layer, but it penetrated the shirt, with a nose-like deformation29 of the undershirt hanging over the hole on the shirt made by the projectile. The projectile itself sits inside the tip of the nose. More shots were fired, and the phenomenon was confirmed beyond any doubt. A few weeks later, we got access to a Redlake HG-100K high-speed dig- ital camera, with a highest frame rate 100,000 frames/sec. The high speed camera painted a vivid story, explaining the “Pinocchio’s nose” phenomenon in terms of the time sequence of the penetration process. The story goes as follows. As soon as the bullet first hit the undershirt, the undershirt began to deform, while the projectile pushed the undershirt forward. The bullet, with the undershirt covering its nose, then impact and penetrated the shirt, and pushed a part of the undershirt through the bullet hole, forming a nose-like deformation. The length of the nose kept increasing, until the undershirt reached its elastic limit and was penetrated by the bullet. Afterwards the undershirt retracted back through the hole on the shirt. If the impact velocity is slightly below the threshold velocity, then the bullet did not have enough kinetic energy to stretch the nose on the undershirt beyond its elastic limit, resulting in the tell-tale Pinocchio’s nose. With the slow-motion pictures, there can be no doubt that, if the March 19 shooting of Chen was not staged, then the lead bullet would have also penetrated Chen’s shirt after it penetrated the undershirt. The “Pinocchio’s nose” effect alone is strong enough to convict Chen of perjury for the March 19 shooting, in our opinion. However, any scientific result in a criminal case, however strong, is subject to attack on the evidence, using unlikely scenarios to raise doubts on the evidence. For instance, Chen’s defenders can say that Chen’s undershirt might be defective in the area around the exit hole, or the area around the exit hole might have been

29Dubbed “Pinocchio’s nose” by one of us.

33 damaged by washing. Well, that undershirt is still in the possession of the CIB, and the strength of the area near the exit hole can be tested. We hope the CIB will perform such a test, against all odds. Even if such a test is performed and no appreciable damage was detected, Chen’s supporters can still say that the defective or damaged area might be very small and not easily detectable. Such low-probability events are discussed in §8.

6 Inconsistent entrance holes

We recall the size of the entrance holes on Chen’s clothing: 1.4 cm long and 0.4 cm wide on the jacket, 2.4 cm long and 0.5 cm wide on the shirt, 1.0 cm long and 0.6 cm wide on the undershirt. The CIB has not described the orientation of the entrance holes in writing. Image analysis of the photographs of the clothing showed that the long axis of the entrance hole on the jacket form an angle about 58◦ with the horizontal base line for the jacket. Photographs taken by a high speed camera show that penetration of fabric by a round-nosed projectile occurs when the fabric was stretched beyond its elastic limit. In our tests, the maximum length of bullet holes on the jacket by the lead bullet can reach 1.4 cm. For the same impact velocity, the shape and size of the bullet hole depend on the orientation of the bullet at impact and the angle between the trajectory and the jacket. The diameter of the hole is about 0.6 cm if the lead bullet strikes the jacket vertically, nose ﬁrst. The 1.4 cm long bullet hole on the jacket indicates that the lead bullet impacted the jacket on its side, and the long axis of the bullet formed an angle close to 58◦ with the horizontal base line of the jacket at impact time. The long axes of the entrance holes on the shirt and the undershirt are basically vertical. The length of the holes are 2.4 cm and 1.1 cm respectively, indicating that the lead bullet impacted them at its side, with the long axis essentially vertical. There are two serious problems when one tries to reconstruct the entrance holes. First, the length of the entrance hole on the shirt, 2.4 cm long, is way too long. The maximal length of bullet hole we could reproduce on the shirt was 1.5 cm under normal circumstances, when the muzzle was at least 10 cm away from the shirt. When the muzzle was in near-contact with the fabric, the size of the bullet hole was enlarged by the airﬂow from the barrel, and

34 can reach 7 cm long. However that scenario does not apply to the March 19 shooting. The shot was not fired within close range according to the CIB. Moreover the five layers of fabrics on the jacket severely limits any possible effect of the airflow from the barrel on the shirt. The second problem is that, the orientation of the bullet changed about 58◦. Suppose the jacket and the shirt was 3 cm apart, and the velocity of the bullet was 180 m/sec, the estimate according to the CIB. That puts the yawing angular velocity at 1,000 complete turns per second, which is impossibly high. Let us compare that angular velocity with the spinning angular velocity of pistols and revolvers, which should be at least several times higher than the angular velocity of the yawing motion. A 9 mm Browning pistol bullet makes 1,340 complete turns per second, a .40 Smith & Wesson pistol bullet makes 714 complete turns per second, and a .38 Smith & Wesson special revolver bullet makes 557 complete turns per second.; see [SK, p. 354]. How can the problems about the entrance holes be explained? The honest way would be to reconstruct the pattern of the entrance holes in an experiment. We will be really surprised if that can be done. What we expect is another attack on the evidence. Perhaps the entrance hole on the shirt was just a bit over 1 cm, but somehow it was enlarged when Chen was undressed in the hospital.30 Or, perhaps the entrance hole on the jacket or the undershirt was enlarged inadvertently by the doctors or nurses, so the estimate of the angular velocity above does not apply. It is all too easy to point to some low-probability event that might have happened to the evidence. Please see §8 for discussions about such defense tactics. Before ending this section, we would like to mention some other features in the damage pattern to Chen’s clothing that we find troublesome.

The distance between the entrance and exit holes on the undershirt was 9 cm, shorter than the length of the wound, which is 11 cm.

There is an L-shaped damage on the shirt, in an area the exiting bullet was likely to have hit. The longer side of that damage measured about 2.6 cm, the shorter side 1.8 cm. If the damage was made by the bullet, than it is way too long again. Nobody can explain this damage.

30That is unlikely, because we know that Dr. Henry Lee asked the a Chi Mei head nurses about how Chen’s clothing was handled, and the head nurses did not know of any incident in which any of the bullet holes might have been enlarged.

35 There are at least four other damaged area on the shirt, besides the entrance hole and the L-shaped damage. Nobody can explain them either.

The CIB has oﬀered no plausible explanation about the mysterious damages on Chen’s shirt, and the question on the distance between the two holes on the undershirt was ignored in their shooting experiment.

7 CIB’s shooting experiment

The CIB released the results of its shooting experiment, conducted two months after Dr. Henry Lee requested it; see page A3 of China Times, June 25, 2004. They used pig skin over a life-sized dummy, covered with clothing. From the pictures released by the CIB it is clear that the shirt used by CIB is different from the shirt Chen wore on March 19. They used pistols with bar- rels replaced by smooth bore tubes, and fired modified bullets with different amounts of propellant. Ten paper boards were placed along the trajectory, one meter apart, to demonstrate the yawing and tumbling of the bullet fired from the smooth bore pistol. The CIB’s test results and conclusions about the lead bullet, based on 3 valid shots, are as follows.

(a) A modified bullet, fired by a modified smooth-bore pistol, yaws and tumbles immediately after leaving the muzzle. In comparison, a bullet fired from a rifled pistol is stable for the first ten meters.

(b) The three valid shots, with 90% propellent, all penetrated the jacket, the shirt and the undershirt, grazed or penetrated the target pig skin, but none penetrated the undershirt or the shirt.

(c) The energy density per unit area of the bullets is 123 J/cm2, far exceeding CIB’s “practical wounding criterion”, 20 J/cm2. Therefore the CIB appraised and determined, that the lead bullet in the March 19 shooting “had enough energy to penetrate clothing and cause graze wound”; the trajectory and the wound “was consistent with the actual situation.”

The details of the CIB’s data were not released; the press reported that the average muzzle velocity of the three valid shots were about 180 m/sec.

36 There are clear deﬁciencies of the CIB shooting experiment:

(1) The most obvious is that they based their conclusion on just three valid shots. With only three data points, how conﬁdent can one be about the result, and how does one determine any meaningful statistical information out of a sample of three?

(2) The CIB used paper board to observe yawing and tumbling of the bullet. The paper board tends to increase the yaw. Moreover they do not give much information. It would be a lot better to use a high speed camera instead.

(3) The CIB did not use the same fabric as Chen’s custom-made shirt.

(4) As tissue simulant, 10% ordnance gelatin at 4 and ballistic soap are superior to pig skin. See [SK, pp. 188–214] for discussion about tissue simulants.

(5) The pig skin used by CIB was taken from butchered animals. It is much tougher than human abdominal skin, therefore not suitable as a skin simulant. It will be much better to use live piglets under anesthesia.31

The CIB did not cite any literature to support their 20 J/cm2 “practical wounding criterion”3233 they use. They only said that it was used by the

31The abdominal walls of piglets under 10 kg are thinner and more tender compared with older pigs. The advantage of live animals versus skin from butchered pigs is clear. 32A property of skin, gelatin, soap or bone is that a projectile with a speed below the threshold velocity cannot penetrate them; see [SK, pp. 217–240], [DM, pp. 258–260]. The threshold velocity depends on the mechanical property of the target as well as the hardness and the shape of the projectile. Of course for a given projectile, the velocity is closely related to the kinetic energy, and also to the kinetic energy per unit area. With the target (skin, gelatin, etc.) ﬁxed, while the projectile varies, the kinetic energy per unit area is a more important factor for penetration, compared with either the velocity or the kinetic energy of the projectile. See Tables 6.1.2 and 6.1.3a for threshold energy density and threshold velocity for various projectiles to penetrate human skin. For instance the threshold energy density for a .38-special round nose bullet is 19.1 J/cm2, and the threshold velocity is 58m/s; see also [DM, p. 250]. 33When translated into Chinese, both “wounding criterion” and “casualty criterion” become the same, causing confusions. The term “casualty criterion” is supposed to be the amount of kinetic energy a normal projectile needs to take a man out of combat; i.e. to incapacitate an enemy. The U.S. Army adopted 58 ft-lb. or 80 J, as a practical casualty criterion during World War II, based on [G]. A casualty criterion, at best, indicates the

37 Japanese police. Also, the CIB did not measure the impact velocity of the lead projectile on the tissue simulant, i.e. the velocity after the lead bullet penetrated the jacket, the shirt, and undershirt; that value, rather than the impact velocity at the jacket, is more relevant to the ability for the lead bullet to penetrate the skin. The most serious problem of the CIB’s experiment lies not with the slop- piness of the design, but with their far-reaching and unqualified conclusion that their three valid shots were “consistent with the actual situation in the March 19 shooting.” If one looks what the CIB actually did in its experiment, all that can be inferred, even with 50 or 100 valid shots, is that a lead bullet of the same shape as the one in 3/19 shooting, if fired with a muzzle velocity about 180 m/s, can perforate the jacket, the shirt, the undershirt, cause some injury, without perforating all the clothing on exit. Let us see what the CIB experiment did not examine or establish. (1) whether there are black burn marks on the wound, (2) possible depth and length of graze wound, (3) damage pattern of exit holes on clothing, (4) comparison of damage pattern of entrance holes on clothing. We know that none of the three valid shots in the CIB experiment penetrated the undershirt on exit. The CIB said nothing about the damage pattern to their tissue/skin simulant, and nothing about the damage pattern of the entrance holes. Despite the scant amount of data and all the above features in the damage pattern not considered, CIB called the result of their shooting experiment “consistent with the actual situation” in the March 19 shooting, without specifying what was meant by that. The normal interpretation of that phrase is, or should be, that the damage pattern of their experiment matches the damage pattern found in the March 19 shooting. What features among the damage pattern caused by the lead bullet in March 19 did the CIB fail to take into account? They include: presence of burn injury, probable effective of a projectile. The values established by major countries differ widely. See [SK, p. 303–313] and [B, p. 111–112] for further discussion about casualty criterion.

38 the shape of the wound,

the length of the wound,

the depth of the wound,

the shape and orientation of the entrance holes on clothing,

the size of the entrance holes on clothing, especially the length of the entrance hole on the shirt,

the shape and size of the exit hole on the undershirt,

whether the shirt was penetrated on exit.

So the CIB completely ignored the pattern of the wound. Just the presence of some wound was good enough for them. Similarly, the size and shape of the entrance holes on clothing was of no significance to the CIB. All it cared about was that there wer three entrance holes on clothing. The exit holes were irrelevant to the CIB officialss, they did not care about them at all, because none of their three valid shots penetrated the undershirt on exit. Yet the CIB declared that their experiment “consistent with the actual situation”. Of course the above features in the damage pattern above the CIB had chosen to ignore allowed them to avoid those inconvenient features in the evidence which cannot be reconstructed no matter how hard they try. To a normal person, a wound 3 cm long and 0.4 cm deep is very different from one which is 11 cm long and 2 cm deep; a wound with burn injury is very different from one without; a hole on a shirt 2.4 cm long is very different from one which is 1 cm long; and the fact that the bullet perforated the more elastic undershirt on exit but was stopped by the much less penetration-resistant shirt is an important damage pattern. Why did the CIB ignored all the prominent features in the damage pattern listed above? This is a question only the CIB can answer. The CIB selectively ignored several important pieces of evidence. When a witness does that in court, it is called perjury.

8 Events with minuscule probability

39 We have presented our argument that the March 19 shooting of President Chen was staged, and we are confident that our scientific analysis will stand. The fact that bullets do not burn the skin is indisputable. As for the scientific arguments supporting the features (B), (C), (D), we challenge the CIB and Chen’s defenders to reconstruct the damage pattern, all of them, in one shot. If the CIB is honest, that is what they should do. That’s what responsible scientists would do. What the CIB and Chen’s defenders are likely to do, instead of challenging our science honestly,34 is to attack our credibility and attack the evidence. They may say that we have no business saying anything about the forensic profession, because we are not licensed practitioners, which is true. They may throw mud on us, saying that we are hired guns, that we work for the Nationalist Party or for the People First Party, which are false. Our answer to the “lack of license attack” is that, whether a scientific statement is true or false is an intrinsic property of the statement itself. Newton’s laws are true not because Newton said so, but because they hold wherever you are and whoever you are. That is the beauty of science. None in our group is a forensic scientist. That does not make what we said any less true. However it is unlikely that you will find an ultimate authority you can rely on about the March 19 shooting, at least no in the immediate future. You, the reader, will have to judge the scientific merit of our argument yourself. We have anticipated the possible attacks on the evidence. That strategy relies on a misleading use of probability. To “explain away” the contradictions with science in the evidence, that attack calls for citing a sequence of unlikely events, saying that they are all possible. Let us see what is logically required of the “attack of evidence” strategy. If one is to argue that Chen is innocent, the following low-probability events must all happen: All physicians who treated Chen’s wound mistook congealed blood for burn marks, or they all lied. Some movement of Chen’s body increased the depth of Chen’s abdominal wound by more than 200%, or all physicians who treated Chen

34Here is an example of unscientiﬁc challenge. The CIB, in a statement on August 9, said that “experiments should be carried out in circumstances similar to those of the March 19 shooting, or they would be worthless in shedding light on the incident”, contradicting both the established practice of terminal ballistics and Newton’s laws.

40 lied.

There is some yet-to-be-discovered conﬁguration of Chen’s abdomen that will facilitate the creation of a graze wound 11 cm long.

The area on Chen’s undershirt close to the exit hole was defective or damaged.

The entrance hole on Chen’s shirt was enlarged in a yet-to-be-identiﬁed event by an unidentiﬁed person.

Either the entrance hole on Chen’s jacket or the entrance hole on Chen’s undershirt was enlarged in some unidentiﬁed event.

If you can believe that the above event all happened, then you will have no trouble believing that the medical staff of Chi Mei Hospital, under influence of collective amnesia, created the five damages on Chen’s shirt, nor that Chen, practicing the virtue of frugality, chose to wear a custom-made shirt with five damaged area on the last day of his reelection campaign, and forgot to give this piece of information to the prosecutor or the CIB afterwards. It is difficult to assign a numerical value for the probability of each of the improbable events above. For the sake of argument, let us say that the probability of each of the events is one in a thousand. Then the probability 18 18 that the six independent events all happened is 10− = 1/10 . To give an idea of the number 1018 (one million trillion, or a billion billion), the number of cells in an adult human is estimated to be between 1013 and 1014, so it takes at least ten thousand adults to get 1018 cells. The flaw of the argument, that any scenario with non-zero probability is possible, therefore cannot be dismissed, can be illustrated in the following example. According to quantum mechanics, it is technically “possible” that all the oxygen molecules within one mile of Washington D.C. disappear together from where they were, and spontaneously appear in New York City, for a whole day. The probability of that event is not zero. We submit that, such an event has never happened in the entire history of the earth, and will not happen before the extinction of Homo sapiens. It is clearly absurd if you take into account such a low-probability event in your decision making. The famous French Mathematician Emile Borel said that an event of probability 1/1050 is a negligible on the “cosmic scale”, and an event with

41 probability 1/1015 is a negligible on the “terrestrial scale”. We strongly advise against buying any lottery ticket in which your chance of winning is 1/1018, no matter how large the jack pot is, because you will not win. The premise of the “attack of evidence” defense for Chen’s innocence is that an event of a vanishingly low probability happened before the eyes of tens of thousands of people. And let us remember that we have not taken into consideration other factors such as the shooter’s marksmanship, the inexplicable decision of Taiwanese secrete service to let the President and the Vice President ride on the same private vehicle, without bullet-proof vests, the extraordinary errors of the secrete service and police to allow the crime scene remain unsecured for several hours after the shooting, and to transport both the President and the Vice President in the same jeep and without extra security after both were shot? Dear reader, Chen’s defenders may try to convince you that all the unlikely events are “possible”, the doctors were all mistaken, inadvertently, both about the burn marks and about the depth of the wound, and they damaged Chen’s clothes in the emergency room, made some bullet holes bigger, and added some new damages. And, an elusive assassin ﬁred a home-made bullet which produced an 11 cm long graze gunshot wound on the abdomen, a world record. Do you really believe that?

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