German Mass Murderers and Their Proximal Warning Behaviors

Home , Assassination, Filicide, Mass killing, Pseudocommando

Journal of Threat Assessment and Management

Mirko Allwinn and Jens Hoffmann J. Reid Meloy Institute Psychology and Threat Management, University of California, San Diego Darmstadt, Germany

The main objective of this study was to analyze mass murder cases committed by adults from a threat assessment perspective, and to identify risk factors and proximal warning behaviors. Therefore, court records of 33 German mass murderers between 2000 and 2012 were systematically evaluated. One major focus was the comparison between psychotic and nonpsychotic offenders. Signiﬁcant differences were found between the 2 groups regarding their choice of weapons, planning behavior, personal crises, personality aspects, and warning behaviors. Nonpsychotic subjects were signiﬁcantly more likely to evidence pathway warning behavior and directly threaten their targets before the attack when compared with the psychotic subjects. Effect sizes were medium to large. All offenders showed multiple proximal warning behaviors prior to their attacks. Findings are interpreted in light of previous studies and for the purpose of enhancing threat assessment protocols of such persons of concern.

Public Significance Statement The study reveals the presence of warning signs in a representative sample of adult German mass murderers and relates the results to the research from the United States. A predisposition to commit an act of deadly violence was noticeable months, years, or even decades in advance in most of the cases, but the specific intent became apparent relatively late in the pathway toward violence, usually within days or weeks before the killings. The work of threat assessment professionals is supported by the study and opportunities for preventing severe violence are identified.

Keywords: mass murder, threat assessment, threat management, warning behaviors, psychosis

Research studies of adult mass murder from a Following the attack on Columbine High behavioral threat assessment perspective are School in 1999, researchers began to analyze rare (Meloy et al., 2004). In contrast, there is a the latter phenomenon with greater sensitivity plethora of such studies of school shootings. than before (Meloy, Hempel, Mohandie, Shiva, & Gray, 2001; Newman, Fox, Harding, Mehta, & Roth, 2004; O’Toole, 2000). The Safe School This document is copyrighted by the American Psychological Association or one of its allied publishers.

This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. Initiative in the U.S. (National Threat Assess- Editor’s Note. Laura Guy served as the action editor for ment Center, 2018; Vossekuil, Fein, Reddy, Bo- this article.—LSG rum, & Modzeleski, 2002), for example, found that most school shootings were planned in ad- Mirko Allwinn and Jens Hoffmann, Institute Psychology vance, and most adolescent shooters communi- and Threat Management, Darmstadt, Germany; J. Reid Meloy, Department of Psychiatry, University of California, cated their intention to third parties, a warning San Diego. behavior called leakage (Meloy & O’Toole, Correspondence concerning this article should be ad- 2011; O’Toole, 2000). Although leakage was dressed to Jens Hoffmann, Institute Psychology and Threat Management, 64222 Darmstadt, Germany. E-mail: Jens usually a false positive, it was often the entry [email protected] point in a case for threat assessors, and formed

1 2 ALLWINN, HOFFMANN, AND MELOY

the scientific rationale over the next decade for The advent of the wide public use of the national safer school programs, such as the “Say Internet in the 1990s, and the acceleration of Something” effort sponsored by parents and social media use a decade later, have left their supporters of victims killed at Sandy Hook El- own mark on mass murder: almost instanta- ementary School in 2012 (www.sandyhook- neous knowledge of such events worldwide, promise.org; Sandy Hook Promise, 2015). Ger- leading to the common misperception that they many also saw its share of school shootings, are more frequent than they are; the appearance such as the ones in Erfurt in 2002 or in Win- of a time-limited contagion effect which is in- nenden in 2009. Germany has the dubious dis- dependent of geographical limitations (Story, tinction of being second only to the United Youssef, Luthans, Barbuto, & Bovaird, 2013); States in actual numbers of school shootings the easily achieved desire on the part of future worldwide since the turn of the century. Re- perpetrators to learn from those who have pre- searchers in Germany have likewise studied the ceded them (Meloy et al., 2015), while at the phenomenon through the analysis of primary same time wanting to attain greater infamy case files (e.g., Böckler, Seeger, & Heitmeyer, through an increased body count or innovative behaviors; the very recent use of visual media to 2010; Böckler, Seeger, Sitzer, & Heitmeyer, capture the event and broadcast it soon after or 2012; Hoffmann, Roshdi, & Robertz, 2009; even instantaneously during the shooting via Meloy, Hoffmann, Roshdi, & Guldimann, live-steaming, or as it is unfolding; and a real 2014; Roth, Böckler, Stetten, & Zick, 2015). increase in the rate of threats as well as deeds Adult mass murder studies have also seen an (Coleman, 2004; Helfgott, 2015; Kostinsky, evolution over the past 20 years, from relatively Bixler, & Kettl, 2001). Mass murderers are us- small sample and case studies (Hempel, Meloy, ing their lethal attack seemingly more often as a & Richards, 1999; Meloy, 1997; Mullen, 2004) communicative act, addressing an online- to larger sample studies (Adler, 2000; Lankford, audience to spread their violent thoughts and 2015; Stone, 2015; Peter & Bogerts, 2012), to acts into the world (Meloy & Genzman, 2016). studies comparing ideological and nonideologi- Suicide, or in some cases, “suicide by cop” can cal mass killers (Gill, Horgan, & Deckert, 2014; be part of the alleged script. Suicide by cop Gill, Silver, Horgan, Corner, & Bouhana, 2016; ultimately means being killed by law enforce- Lankford, 2013;). Some single case studies with ment. The offender provokes the police (Dewey a particular focus on threat assessment were et al., 2013; Knoll, 2012; Mohandie, Meloy, & also completed (Hoffmann & Allwinn, 2016; Collins, 2009;). Meloy, Habermeyer, & Guldimann, 2015). More similarities than differences are found Prevalence in Germany and the U.S. across various samples of adult mass murderers. Some school shootings and mass killings by Rampage killings are typically defined in the adults in a public space can also be described by U.S. as the intended murder of three or more the superordinate terms “amok” or “rampage.” victims within one event and one general loca- For example, the concept of amok, originating tion, although definitions have varied (Blair & in southeastern Asia, appears to be independent Schweit, 2014; Dietz, 1986). The current active of time (Hoffmann & Allwinn, 2016; Wester- shooter studies from the FBI focus on “an indi- meyer, 1982), culture (Adler, 2015; Hempel, vidual actively engaged in killing or attempting This document is copyrighted by the American Psychological Association or one of its allied publishers. Levine, Meloy, & Westermeyer, 2000), and to kill people in a confined and populated area,” This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. geographical regions (Hempel et al., 1999). On rather than just counting the number of dead the other hand, cultural aspects (Adler, 2015) victims. This definition is comparable with Ger- and cultural scripts (Helfgott, 2015; Kiilakoski man research studies from Adler (2015), & Oksanen, 2011; Newman et al., 2004; Sumi- wherein research findings suggest that about ala & Tikka, 2011) can shape specific details of 5.67 rampage killings happen in Germany every rampage shootings (Douglas & Olshaker, 1999; year. In the decade between 2001 and 2010, 63 Helfgott, 2015), including the perpetrator’s ap- rampage killings occurred. The prevalence rate pearance and his chosen modus operandi (Helf- for males who commit mass murder in the Ger- gott, 2015; Meloy & Mohandie, 2001; Surette, man population was therefore 1:6,800,000 per 2002, 2016). year, an extraordinarily infrequent event which GERMAN MASS MURDERERS AND THEIR WARNING BEHAVIORS 3

statistically precludes prediction (Adler, 2015). Rampage shootings by adults were mostly These shootings in Germany produced 94 planned (Gill et al., 2017; Hoffmann & Dölitz- deaths and over 291 injuries. sch, 2015) and the perpetrators often seem to be In the U.S., rampage killings in public spaces preoccupied with weapons (Hempel et al., happen more than once a month. Researchers 1999; Stone, 2015). Many mass murderers con- identified 200 active shooter events between sume drugs or alcohol before their attack (Gill 2000 and 2015 with a rate of 12.5 per year et al., 2017). In early samples of adult mass (Blair & Schweit, 2014; Schweit, 2016). The murderers, the occurrence of psychotic mental numbers did not include school shootings, gang illnesses was much more frequent when com- violence, domestic violence such as familicides, pared with adolescent mass murderers (Meloy or drug related incidents. The shootings in the et al., 2004). Frequency of psychosis in adult U.S. produced 1,274 casualties including the mass murderers at the time of the event appears wounded and killed, but excluding the perpetra- to vary between 20% and 40% (Adler, Marx, tors. Seventy-nine shooters (39.5%) killed three Apel, Wolfersdorf, & Hajak, 2006; Hempel et or more victims at the scene and met the more al., 1999; Hoffmann & Dölitzsch, 2015; Stone, limited criteria for a mass killing. Eighty shoot- 2015). Psychotic offenders are also more likely ers (40%) committed suicide through either to target strangers (Adler, Lehmann, Räder, & self-inflicted wounds or “suicide by cop.” Ram- Schünemann, 1993; Hempel et al., 1999; Peter page murders in the U.S. account for only 0.1% & Bogerts, 2012), have a greater lethality risk of homicides, which are invariably one perpe- since they kill more victims (Dietz, 1986; Hem- trator and one victim, usually known to each pel et al., 1999), and regularly express a para- other. There are approximately 30 single victim noid mindset (Hempel et al., 1999; Knoll & homicides a day utilizing a firearm as the Meloy, 2014; Stone, 2015). Approximately half weapon of choice in the U.S. (FBI UCR, 2015). of mass murderers studied were suicidal and Studies from Germany (Adler, 2015) and the killed or tried to kill themselves immediately U.S. (Blair & Schweit, 2014; Schweit, 2016) after the attack (Gill et al., 2017; Hempel et al., show that rampage killings are significantly 1999; Hoffmann & Dölitzsch, 2015). Suicide is higher in the U.S. than in Germany. The differ- clearly more frequent than in some other forms ences between the U.S. and Germany is partly of targeted violence, such as public figure at- due to much more restricted gun control in tackers (Hoffmann, Meloy, Guldimann, & Germany and the wide and easy availability of Ermer, 2011; Meloy & Amman, 2016). firearms within the U.S. (Lankford, 2015). The U. S. Department of Justice and the Federal Bureau of Investigation published a re- Characteristics and Risk Factors and cent study of preattack behaviors of active Behavior of Concern shooters in the U.S. between 2000 and 2013 (Silver et al., 2018). Over 63 active shooter The studies, although limited to date, reveal cases were analyzed. The definition for an ac- interesting characteristics of the offenses and tive shooter was “an individual actively en- offenders. Perpetrators are almost always men gaged in killing or attempting to kill people in a and reflect the ethnic composition within soci- confined and populated area” (Blair & Schweit, ety at large (Gill, Silver, Horgan, & Corner, 2014). An implicit criterion was the use of 2017; Hempel et al., 1999; Lankford, 2015; firearms. Shootings that resulted from gang or This document is copyrighted by the American Psychological Association or one of its allied publishers. Silver, Simons, & Craun, 2018). The average drug violence or organized crime were ex- This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. educational attainment is relatively low (Gill et cluded. The majority of the shooters spent more al., 2017; Hempel et al., 1999). The unemploy- than a week planning their attack (77%). Nearly ment rate seems to be higher compared with the half of them (47%) spent a week or longer general population. In addition, there are fewer actually preparing for the attack. These results partnerships and more single men (Gill et al., are comparable with those of other studies (e.g., 2017; Hempel et al., 1999; Silver et al., 2018). Gill et al., 2017). Psychiatric diagnoses were Recent mass murder studies indicate a higher available for 25%, but only 3% were diagnosed previous criminal conviction rate among the with a psychotic disorder. Multiple stressors perpetrators (Gill et al., 2017; Silver et al., (3.6 in average) were evident, mostly mental 2018). health problems (62%), financial strains (49%), 4 ALLWINN, HOFFMANN, AND MELOY

or job issues (35%). Only 2% (n ϭ 1) seem to outcome of an attack. Out of the 43 cases, 10 have had no stressors during the 12 months did not meet the above criteria and were there- before the shooting. The active shooters dis- fore excluded from the final sample. The final played concerning behaviors like leakage of dataset of 33 cases was statistically analyzed to violent intent, anger, or physical aggression. identify potential risk factors, warning behav- Inappropriate firearm behavior—interest in or iors and other characteristics of German ram- use of firearms that appears unusual given the page killers using SPSS 21 (IBM Corporation, active shooter’s background and experience 2012) with ␣ϭ.05 unless otherwise indicated. with firearms—was shown by one in five shoot- Common statistical significance tests were per- ers (21%). In nearly two thirds of the cases formed to determine the group differences. To (64%) at least one of the victims was specifi- test the central tendency in non-normally dis- cally targeted by the shooter. The weapons were tributed, at least ordinally scaled data, the Mann mostly purchased legally (40%). In hindsight, & Whitney (1947) U test was applied. The knowing that they ended up carrying out an attack, concerning behavior in the 12 months Fisher and Yates (1948) exact test was used for leading to the attack could be identified for the significance testing on dichotomous variables majority of the shooters (64%). The question because, unlike the chi-square test, no particular whether or not this behavior could have been sample size is required and the Fisher’s exact identified as concerning before the attack re- test can also be used for small samples. mains to be answered. Nearly half of the shoot- All cases were analyzed by the first author ers displayed suicidal ideation or engaged in with the same codebook consisting of 235 vari- suicide-related behaviors at some point prior to ables. A prior interdisciplinary study analyzing the attack (48%). interrater reliability showed good results (Göbel et al., 2016). Most of the variables showed kappa values over .60 (n ϭ 209). Some vari- Method ables (n ϭ 26) had kappa values under .60 but We identified relevant cases for this study in remained in the codebook due to their substan- Germany in two steps. First, a media database tial relevance for the research project. The co- search for the identification of potential adult debook was divided into 11 sections: basic in- mass murder cases was carried out. In a second formation (n ϭ 13), demographics (n ϭ 15), the step, the full case files for all identified attacks violent act (n ϭ 85), warning behaviors (n ϭ were requested. Of the 60 cases identified, 43 21), criminal record (n ϭ 28), psychiatric record case files (72%) were sent to us by the public (n ϭ 12), personality traits (n ϭ 9), radicaliza- prosecution departments throughout Germany. tion (n ϭ 6), affinity for violence and weapons Cases for the study were selected based upon (n ϭ 10), family (n ϭ 17), and social risk and the following criteria: protective factors (n ϭ 13).

1. the attack was carried out between Janu- Quality of Data and Missing Data ary 1, 2000 and December 31, 2012, and 2. at least partially happened in public space. The court ﬁles used to assess each case dif- 3. The perpetrator was older than 24 years. fered in the quantity and quality of material

This document is copyrighted by the American Psychological Association or one of its allied publishers. 4. The perpetrator had tried to kill more than provided. The number of pages per case ranged This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. one person. from 400 to 6,000. All of the court ﬁles con- 5. Killings in the context of organized crime, tained witness statements. Psychological reports or attacks carried out by members of ter- (n ϭ 18, 55.5%), court rulings (n ϭ 21, 63,6%), rorist organizations, as well as attacks ϭ committed using only vehicles were investigation reports (n 28, 85.8%), or per- excluded. sonal documents such as letters, manifestos, or suicide notes (n ϭ 21, 63.6%) were mostly Unlike other studies, we focused not only on available. Due to the variations in quality and successful rampages but also intended mass quantity of data per case, the full dataset con- murders. The intention of killing more than one tains 22.4% missing data. Table 1 shows the person was decisive for us, and not just the missing data for each section. GERMAN MASS MURDERERS AND THEIR WARNING BEHAVIORS 5

Table 1 family or other associates of the object of Missing Data Per Section fixation, if present and aware; and (e) angry Percentage emotional undertone. It is typically accom- Number of missing panied by social and/or occupational dete- Section of items data rioration. 1) Basic information 13 .00 • Identification warning behavior: is charac- 2) Demographics 15 5.86 terized by one or more of five characteris- 3) The violent act 85 18.57 tics: pseudocommando behavior (Dietz, 4) Warning behaviors 21 8.26 1986), evidence of a warrior mentality 5) Criminal record 28 43.64 (Hempel et al., 1999), a close association 6) Psychiatric record 12 34.85 with weapons or other military or law en- 7) Personality traits 9 20.88 8) Radicalization 6 15.76 forcement paraphernalia, wanting to imi- 9) Affinity for violence and tate and often surmount previous attackers weapons 10 13.03 or assassins, or believing oneself to be an 10) Family 17 38.32 agent to advance a particular cause or be- 11) Social risk and protective factors 13 38.86 lief system (Meloy et al., 2015). • Novel aggression warning behavior:anact of violence which appears unrelated to any Warning Behaviors pathway warning behavior which is committed for the first time. Such behaviors One major focus was the evaluation of the may be utilized to test the ability (de eight warning behaviors described in the warn- Becker, 1997) of the subject to actually do ing behavior typology (Hoffmann et al., 2011; the violent act, and may be a measure of Meloy, Hoffmann, Guldimann, & James, 2012) response tendency, the motivation to act on within our sample of psychotic and nonpsy- the environment (Hull, 1952), or a behav- chotic offenders. The typology captures proxi- ioral tryout (MacCulloch, Snowden, Wood, mal behavioral or psychological patterns which & Mills, 1983). may constitute change and evidence accelerat- • Energy burst warning behavior:anin- ing risk. The original studies reviewed in detail crease in the frequency or variety of any the previous research which attempted to iden- noted activities related to the target, even if tify these acute and dynamic variables among the activities themselves are relatively in- attackers and assassins of celebrities, politi- nocuous, usually in the hours, days, or cians, and other public figures, psychiatric pa- weeks before the attack (Odgers et al., tients, adolescent mass murderers and school 2009). shooters, adult mass murderers, spousal homi- • Leakage warning behavior: the communi- cide perpetrators, workplace violence attackers, cation to a third party of an intent to do and federal judicial threateners and attackers harm to a target through an attack (Meloy (Meloy et al., 2012, 2014). It is a rationally & O’Toole, 2011). derived typology consisting of the following • Last resort warning behavior: evidence of warning behaviors: a “violent action imperative” or “time im- • Pathway warning behavior: any behavior perative” (Mohandie & Duffy, 1999); in- that is part of research, planning, prepara- creasing desperation or distress through This document is copyrighted by the American Psychological Association or one of its allied publishers. tion, or implementation of an attack (Cal- declaration in word or deed, forcing the This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. houn & Weston, 2003; Fein & Vossekuil, individual into a position of last resort. 1998a, 1998b, 1999). There is no alternative other than violence, • Fixation warning behavior: any behavior and the consequences are justified (de that indicates an increasingly pathological Becker, 1997). preoccupation with a person or a cause • Directly communicated threat warning be- (Mullen et al., 2009). It is measured by: (a) havior: the communication of a direct increasing perseveration on the person or threat to the target or law enforcement because; (b) increasingly strident opinion; (c) forehand. A threat is a written or oral com- increasingly negative characterization of munication that implicitly or explicitly the object of fixation; (d) impact on the states a wish or intent to damage, injure, or 6 ALLWINN, HOFFMANN, AND MELOY

kill the target, or individuals symbolically perpetrators were in almost every case un- or actually associated with the target. masked (97%). However, seven offenders (21.2%) were described as having a peculiar Results appearance during the attack, for example, wearing clothes that seemed odd regarding Demographic Characteristics color or combination of clothes, or did not fit the season of the year. Virtually all of the 33 mass murders were Victims committed by a single offender (97%). Only one act was carried out by a couple, but the A total of 121 persons were either killed or female was excluded from our sample because injured by the 33 offenders, ranging from one to she did not meet the minimum age criterion of 19 victims within one act of violence. Thirty- being at least 25-years-old. Thirty-one perpetra- five individuals died (M ϭ 1.06; SD ϭ 1.03) tors (93.9%) were male with ages ranging from and 86 people were injured (M ϭ 2.60; SD ϭ 26 to 78 years. The mean age was 46.82 years ϭ 2.99). Twelve attacks (36.4%) had no deaths, 11 (SD 12.68); 19 offenders (57.6%) were be- led to one death, six offenses claimed two tween 30 and 50 years of age. deaths, and four cases led to three deaths. The Two thirds of the mass murderers (66.7%) range of injuries was 0–16 across the attacks. In were German citizens and 33.3% were non- one case, an explosion in an apartment building natives that had immigrated between 1965 and caused 16 injuries. 1996. Nearly half of the offenders (45.5%) were unmarried, 12 were married (36.4%), and six Planning were divorced (18.2%). The level of education varied broadly and For a better understanding of the develop- covered the full range of educational qualifica- ment of the offenses, we analyzed the period of tion achievable in Germany. Information about planning for the attacks, starting from the first the educational career was available for 26 per- idea until the beginning of the mass murder. petrators. Five (19.2%) did not have any school Some attacks were planned well in advance, and education, nine (34.6%) had a lower level of others occurred rather spontaneously. In 31 education (main school/lower secondary educa- cases, the files provided us with enough detailed tion), seven finished middle school, and five information to be able to assess the time period (19.2%) graduated high school. Nearly half of for planning and preparation behavior. Sixteen the mass murderers (48.5%) were unemployed (51.6%) perpetrators planned their attack for at the time of the attack. Four (12.1%) were weeks, months, or even years. In four cases unemployed and three (9.1%) were retired. (12.9%), the offenders decided to commit the Nearly a third of the offenders were employed violent act within 24 hr of the offense. More or at least marginally employed at the time of than one third (35.5%) committed their rampage the attack. without any evidence of planning. Table 2 gives Two of the perpetrators were adopted. At the an overview of planning behavior in our sam- time of the attack, nearly half of the perpetrators ple. (49.5%) had children. Eighteen (54.5%) lived When information was available, a more in-

This document is copyrighted by the American Psychological Association or one of its allied publishers. alone, the remaining 45.5% mainly shared a depth analysis of the longer planned mass mur-

This article is intended solely for the personal use of the individualhousehold user and is not to be disseminated broadly. with their intimate partners or spous- ders (see Table 3) reveals the time frame, start- es. The vast majority had a permanent resi- ing with the ﬁrst ideas, communicated to third dence, but three offenders (9.1%) were home- less. Table 2 Circumstances of the Offense Planned Versus Unplanned Mass Murders (N ϭ 31)

Nearly half of the attacks (45.5%) were car- Planning behavior % ried out in more than one location. In these Longer planned (Ͼ24 hr) 51.6% cases, most of the perpetrators moved from a Shortly planned (Ͻ24 hr) 12.9% building to a public space (12 out of 15). The Unplanned 35.5% GERMAN MASS MURDERERS AND THEIR WARNING BEHAVIORS 7

Table 3 review of all testimonies also allowed to clas- Pathway Behavior: Beginning of Violent Ideation sify the cases based on psychotic symptoms. and Earliest Planning and/or Preparation for the The psychotic perpetrators were in an acute Attack (N ϭ 16) psychotic episode during their crime based on Earliest the case material. Independently, these perpe- Beginning evidence of trators also had psychotic episodes in their past. with violent planning and Among the nonpsychotic perpetrators, there ideation preparation was no evidence of a past or present psychotic ϭ ϭ (N 15) (N 16) episode or disease. Time period n % n % The gender distribution between the psy- 1–7 days 0 0 5 31.3 chotic and nonpsychotic perpetrators was unre- 1–2 weeks 1 6.7 4 25.0 markable; each group contained one female. 2–4 weeks 1 6.7 5 31.3 Psychotic perpetrators (M ϭ 44.64, SD ϭ 1–3 months 1 6.7 1 6.3 13.46) were slightly younger than the nonpsy- 3–6 months 1 6.7 0 0 chotic perpetrators (M ϭ 48.37, SD ϭ 13.04), 6–12 months 5 33.3 1 6.3 although the difference was not significant. The More than 1 year 6 40 0 0 marital status differed significantly (⌽ϭ.59, p ϭ .002) with a large effect size: Psychotic perpetrators were mostly single (n ϭ 9), while parties in most cases (leakage), until the first nonpsychotic individuals were often married ϭ pathway behaviors. In six cases, more than 1 (n 15). In addition, most of the nonpsychotic year passed between the earliest signs of ide- offenders had children (68.4%), whereas fewer ation with a murderous act and the first signs of psychotic subjects had children (18%); the dif- planning and preparation (Calhoun & Weston, ference was significant with a large effect size ϭ ⌽ϭ 2016, 2003). The final decision to commit the (p .021, .484). act mostly evolved within a few weeks before Most psychotic (81.8%) and nonpsychotic the attack. Most perpetrators (n ϭ 14, 87.5%) subjects (63.2%) were unemployed. The occu- showed the earliest evidence of planning and pational difference was nonsignificant between ⌽ϭ ϭ preparation between 1 day and 4 weeks before both groups ( .196, p .419). The educa- their act of violence. tional level for both groups was similar and ϭ Examples for the earliest signs of violent nonsignificant regarding school, U (13,10) ϭ ideation are thinking about attacking or killing 70, p .784; and vocational education, U ϭ ϭ someone, or the paranoid fear that one’s own (13,10) 48.5, p .288. life is in danger, combined with thoughts about Attack Characteristics self-defense. Possible evidence of planning and preparation were, for example, carrying a Attack characteristics are listed in Table 4. weapon, developing a plan of where to attack, The two groups only differed significantly re- or writing a suicide note. garding the planning of the violent act (p ϭ .006, ⌽ϭ.544), with a large effect size. The Psychotic Versus Nonpsychotic Mass majority of the nonpsychotic subjects planned Murderers their act in advance (63%), while only one in 10

This document is copyrighted by the American Psychological Association or one of its allied publishers. psychotic subjects did so. In our sample, 36.7% (N ϭ 11) of the Ger- This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. man mass murderers were psychotic, 63.3% Weapons (N ϭ 19) were nonpsychotic, and three perpetrators could not be reliably classified as either, Seven attacks were committed with more and were therefore excluded from the compar- than one weapon, with the number of weapons ison. The classification as “psychotic” was ranging from two to nine (M ϭ 3.71). Twelve made after the complete review of the file. In perpetrators (40%, N ϭ 30) carried at least one several cases, the person was diagnosed with a additional weapon with them which they did not schizophrenic disease during his or her lifetime use during the attack. There was no significant or after his or her death by court experts. Pre- difference between the psychotic and nonpsy- vious psychological assessments and a detailed chotic offenders regarding the two factors “use 8 ALLWINN, HOFFMANN, AND MELOY

Table 4 Attack Characteristics of Nonpsychotic and Psychotic Offenders

Nonpsychotic Psychotic Attack characteristics offenders N offenders N More than one location 37% 19 64% 11 Occurred in public 53% 19 73% 11 Public building 53% 19 64% 11 Private building 37% 19 27% 11 At the workplace 11% 19 0% 11 Offender was masked 5% 19 0% 11 Peculiar appearance 16% 19 27% 11 10 %9 19 %63 ءAct was planned in advance .p Ͻ .05 ء

of multiple weapons” and “carrying more weap- murder weapon. Most weapons were procured ons than used.” In total, 16 perpetrators (53.3%) by nonpsychotic offenders (n ϭ 11; 73.34%) carried and used only one weapon, 14 (46.7%) over half a year before the act. For three psy- used more than one weapon and/or carried more chotic offenders (42.86%), the time of arms weapons with them without ever using them. procurement was more than six months prior. The psychotic and nonpsychotic offenders dif- Here are two examples of different time fered regarding their choice of weapon (see frames in which the offenders organized their Table 5). Psychotic offenders chose cutting and weapons: stabbing weapons (⌽ϭ.489, p ϭ .015), A 34-year-old psychotic offender took an ax whereas nonpsychotic offenders more fre- in a hardware store, started screaming and run- quently chose firearms (⌽ϭ.489, p ϭ .015). ning around and attacked two strangers. He was Explosives and other kinds of weapons were subsequently retained by witnesses without re- rarely chosen, and did not significantly differ sistance until police arrived. The offender was between the two groups (p ϭ 1.0). diagnosed with paranoid schizophrenia. There Another difference appeared regarding the were no planning and preparation warning be- time of the weapon purchase, but information haviors in advance. was only available for 15 of the nonpsychotic A 52-year-old nonpsychotic offender entered and seven of the psychotic offenders (see Table a restaurant with his girlfriend in 2011. He had 6). In more than one quarter of all cases, no taken his girlfriend hostage the day before. He information was available (26.67%, n ϭ 8). was armed with a pistol, a pump action shotgun, Two (13%) of the nonpsychotic and three a carbine, and a machete. In the restaurant, he (42.9%) of the psychotic mass murderers pur- first read a speech and then started firing at chased their weapon within 24 hr of their attack, people with his pistol. One person was killed but this was not a statistically significant differ- and another person was injured. The perpetrator ence (p ϭ .274). Within 6 months of the of- had made the final decision to commit the offense, two nonpsychotic (13.34%) and one psy- fense during the last 12 hours before the act. He chotic offender (14.29%) obtained their later had previously experienced a series of crises This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. Table 5 Weapons Used by Nonpsychotic and Psychotic Rampage Offenders

Nonpsychotic Psychotic Weapons used offenders N offenders N 11 %36 19 %84 ءFirearms 11 %64 19 %16 ءCutting and stabbing weapons Explosives 11% 19 9% 11 Other weapons 13% 16 14% 7 .p Ͻ .05 ء GERMAN MASS MURDERERS AND THEIR WARNING BEHAVIORS 9

Table 6 their victims, U (18,11) ϭ 48.0, p ϭ .021, r ϭ Time of the Weapon Purchase Before the Act .470. None of the psychotic offenders in our Nonpsychotic Psychotic sample killed a (former) intimate partner, dif- offenders offenders Total fering significantly from the nonpsychotic of- Weapon fenders, U (19,11) ϭ 55.5, p ϭ .033, r ϭ .487. purchase n % n % N % The acts were also distinguished regarding Immediate 2 9.09 3 13.64 5 22.73 prior selection of the victims. Most nonpsy- Ͻ1 week 1 4.55 0 .00 1 4.55 chotic offenders (n ϭ 17, 89.47%) targeted at Ͻ1 month 0 .00 1 4.55 1 4.55 Ͻ6 months 1 4.55 0 .00 1 4.55 least one specific victim on purpose. On the Ͼ6 months 11 50.00 3 13.64 14 63.64 other hand, only one of the 10 psychotic offend- 15 68.18 7 31.82 22 100 ers attacked a specifically selected victim (n ϭ 1, 9.1%). The groups differed significantly (⌽ϭ.79, p ϭ .000). and also had suicidal intentions for some time. Intoxication During the Attack He had purchased the pistol in the 1990s and received the carbine in 2000 in exchange for One third of the offenders (n ϭ 11; 33%) drugs. The shotgun was acquired abroad, the were intoxicated during the mass murder, with- exact time remains unknown. Since the 1970s, out an observable difference between the groups the shooter had been criminally convicted sev- of psychotic and nonpsychotic perpetrators eral times, mostly for drug offenses. Overall, he (n ϭ 4 vs. n ϭ 7); U (19,11) ϭ 107, p ϭ .933. had spent more than 15 years in prison. Alcohol was the biggest contributor to intoxi- cations (n ϭ 9), whereas medications (n ϭ 3), Victims cannabinoids (n ϭ 2), and drugs (n ϭ 1) played a mirror role. Four offenders combined two A total of 112 persons were either killed or different substances (e.g., alcohol and cannabi- injured by the 19 nonpsychotic and the 11 psy- noids). chotic offenders, ranging from one to 19 victims within one attack. Twenty-seven individuals Homicide-Suicide were killed (M ϭ 1.42; SD ϭ 1.02) by nonpsychotic and six by psychotic mass murderers Among the 30 offenders, 15 (50%) attempted (M ϭ 0.55; SD ϭ 0.82). Forty-five individuals or succeeded in taking to their own lives (see were injured by nonpsychotic (M ϭ 2.37; SD ϭ Table 9). Nine perpetrators (30%) were success- 3.88) and 34 by psychotic attackers (M ϭ 3.09; ful and six survived their suicide attempt. SD ϭ 2.26). Eleven (57.9%) nonpsychotic and four psy- Rampages committed by psychotic mass chotic offenders (36.4%) tried to kill them- murderers caused fewer fatalities than those selves. The suicidal behavior was statistically committed by nonpsychotic mass murderers, U nonsignificant between both groups (p ϭ .449). (19,11) ϭ 52.5, p ϭ .023, r ϭ .429, with a Seven out of 11 (63.6%) suicides attempted by medium effect size. The number of injured vic- nonpsychotic and two out of four (50%) sui- tims, U (19,11) ϭ 138.5, p ϭ .132, and the total number of victims, injured as well as dead, did

This document is copyrighted by the American Psychological Association or one of its allied publishers. not differ between the two groups, U (19,11) ϭ Table 7

This article is intended solely for the personal use of the individual109, user and is not to be disseminated broadly. p ϭ .843, and are presented in Table 7. Comparison of Victims Between Nonpsychotic and Psychotic Rampage Killers The Offender–Victim Relationship Nonpsychotic Psychotic offenders offenders The relationship between the offenders and the victims revealed differences between the Victims MSDMSD two groups (see Table 8): Psychotic offenders Injured 2.37 3.88 3.09 2.26 82. 55. 1.02 1.42 ء typically attacked people unknown to them in a Dead public space, U (18,11) ϭ 174, p ϭ .000, r ϭ Victims in total (dead .634, whereas the nonpsychotic offenders usu- & injured) 3.79 3.88 3.64 2.06 .p Ͻ .05 ء ally had some sort of actual relationship with 10 ALLWINN, HOFFMANN, AND MELOY

Table 8 Offender–Victim Relationship in Nonpsychotic and Psychotic Offenders

Nonpsychotic offenders Psychotic offenders (N ϭ 19) (N ϭ 11) Offender–victim relationship MSDnMSDnTotal 49 35 2.32 3.18 14 94. 78. ءStrangers Professional relationship .21 .63 4 .27 .90 3 7 10 0 00. 00. 10 61. 53. ءFormer) intimate) Relatives .53 .23 1 .00 .00 0 1 28 2 60. 18. 26 1.69 1.44 ءAcquaintance Total 55 40 95a a 17 persons could not be assigned to one of the categories. .p Ͻ .05 ء

cides attempted by psychotic offenders were mentioned that the most common homicide- successful, albeit the difference between the suicide forms are within close relationships two groups regarding the relation of successful like spousal murder-suicide, filicide-suicide, and nonsuccessful suicides was nonsignificant and familicide-suicide, and less frequent for (p ϭ 1.0). extrafamilial homicide-suicide. Among the 15 suicidal offenders were four offenders (25%) who tried to provoke the police Criminal Records and History of Mental to kill them. This kind of behavior is referred to Illness as “suicide by cop” (Mohandie et al., 2009). Fourteen perpetrators had a criminal record Two out of these four offenders died at the before their intended mass killing. Psychotic hands of policemen because they posed an im- (n ϭ 2, 20%) and nonpsychotic offenders (n ϭ mediate threat to others; the remaining two were 12, 66.7%) differed significantly in their crimi- not killed, but arrested. Two of the four offend- nal records (⌽ϭ.447 p ϭ .046) with a medium ers were psychotic, and two were nonpsychotic; effect size. Nonpsychotic perpetrators were one perpetrator in each group was killed by an more often known to the police. Prior offenses armed officer. were most likely to be physical assaults, fol- A slight correlation occurred regarding the lowed by property crimes and minor acts like relationship between victim and offender: the road traffic offenses, drug offenses, and resis- number of suicide attempts and successful tance to state violence. suicides was more frequent for closer rela- A history of mental illness and mental re- tionships like relatives or intimate partners cords were also known for both groups. Seven (77.8%) than in cases without an intimate (63.6%) psychotic offenders and seven (36.8%) relationship or family connection with the nonpsychotic offenders had seen a psychologist victims (37.5%). The difference was nonsig- or psychiatrist at some point in the past. In nificant (⌽ϭ.359, p ϭ .057). Liem (2010) many nonpsychotic cases (n ϭ 9, 47.4%), no information was available. Three psychotic This document is copyrighted by the American Psychological Association or one of its allied publishers. (42.8%) and four nonpsychotic attackers This article is intended solely for the personal use of the individualTable user and is not to be disseminated broadly. 9 Suicides and Suicide Attempts Between Psychotic (57.1%) had abandoned their treatment by and Nonpsychotic Offenders Immediately After themselves without recommendation of the Their Attack medical personnel. According to their mental health records, two psychotic and two nonpsy- Nonpsychotic Psychotic chotic perpetrators had made a serious suicide offenders offenders attempt at some point before their violent act. Suicide (N ϭ 19) (N ϭ 11) Suicide attempt 4 21.1% 2 18.2% Warning Behaviors Successful suicide 7 36.8% 2 18.2% Warning behaviors (Hoffmann & Roshdi, Total 11 57.9% 4 36.4% 2015; Meloy et al., 2012) were analyzed for the GERMAN MASS MURDERERS AND THEIR WARNING BEHAVIORS 11

groups of psychotic (N ϭ 11) and nonpsychotic effect sizes were medium and large, respec- (N ϭ 19) offenders. In every case, at least one tively. Direct death threats were uttered by non- warning behavior was detectable; on average, 5.18 psychotic (71.6%, n ϭ 12) as well as by psy- (SD ϭ 2.85) and 6.11 (SD ϭ 2.61) warning be- chotic perpetrators (18.2%, n ϭ 2), resulting in haviors per case were present in the psychotic and a significant difference with a large effect size nonpsychotic mass murderers, respectively, and (⌽ϭ.501, p ϭ .018). In 11 out of 12 nonpsy- the difference was nonsignificant (p ϭ .109). The chotic cases the perpetrator repeatedly commu- number of warning behaviors in a single case nicated direct death threats, whereas psychotic ranged from two to eight in both groups. Figure 1 perpetrators communicated death threats only shows the distribution of warning behaviors in the once (⌽ϭ.580, p ϭ .001). sample. Below are examples of psychotic and non- Two warning behavior patterns differed sig- psychotic offenders’ direct death threats and nificantly between the psychotic and nonpsy- leakage. chotic mass murderers: Pathway warning A psychotic subject spoke with a friend about behavior was more frequent among the nonpsy- his daily routine. He mentioned that he had chotic mass murderers (⌽ϭ.40, p ϭ .0.06). cleared his balcony from the snow with a knife Direct death threat warning behavior was much and said that “you can’t know who is going to more frequent in the nonpsychotic mass mur- attack you.” Meanwhile, he insulted passers-by, derers as well (⌽ϭ.501, p ϭ .018). The saying “Go to hell, soon you’ll all be in for it, warning behavior “direct threat” was slightly you’ll see what comes of it, you all just don’t altered to “direct death threat” compared with want to get your hands dirty.” He also threw a the original work (Meloy et al., 2012). The big bread knife out of the open window while This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.

Figure 1. Warning behaviors of psychotic and nonpsychotic German rampage killers. Annotation: The warning behavior “direct threat” was slightly altered to “direct death threat” in the context of the research work compared with the original work (Meloy et al., 2012). The frequency of direct threats within the present study is therefore underestimated because of the higher speciﬁcation. 12 ALLWINN, HOFFMANN, AND MELOY

listening to metal music. In his delusion, he fenders. As an example, a psychotic perpetrator thought that the devil or evil had taken the shape told relatives that “If someone attacks me, I will of passing birds, so he tried to blind them using get even with them. And if I get killed, it the reflection of the sun in the blade of the knife doesn’t matter, you only die once.” He told before throwing it, because he was convinced family members that he was being harassed on that they were trying to attack him. He then the phone and that he was once called to the descended into the delusion that the devil had company car park. He also believed that “the now taken the shape of one of the people pass- Pole” [a colleague of Polish origin] was after ing by his balcony. Shortly before 2 p.m. on the him and in possession of a weapon, which made day of the attack (which happened at 2:20 p.m.), him feel threatened by him. witnesses saw the offender walking up and Another psychotic offender didn’t care about down the street, leaving a confused impression, his mother, but repeatedly went to see her over while uttering “At some point, you’ll all be in the years to get money from her, which he for it.” mainly used for drugs. He successfully black- A nonpsychotic subject was fined for pos- mailed her by threatening to do “something that sessing a firearm without a permit. During a she would read about in the paper” if she didn’t court hearing he interrupted the judge repeat- give him the money. After she once refused to edly, inter alia saying “This whole thing is a do so, he crushed the tires and broke the win- show trial.” He then requested the judge to state dows of strangers’ cars. He is said to have stated his name. The present attorney stated the to his mother that he would derail trains if she judge’s name, whereupon the defendant turned refused to fulfill his demands. toward the door and shouted “I’ll shoot you A nonpsychotic perpetrator repeatedly down” at the judge. Then he pointed to the threatened employees of his small business. A prosecuting attorney’s representative and de- former employee described the process as fol- clared “And you too”. He then left the board- lows: The offender would regularly drink al- room. On another occasion, this offender came cohol in the mornings, and when something into dispute with a gas station clerk about a would bother him, he would become verbally returnable bottle she didn’t accept. He then abusive. He would then yell and throw tan- poured soda on some of the items on the coun- trums and repeat over and over again that he ter, making them unusable. When the clerk was going to kill everyone and anyone, and wanted to call the police, he told her that if she that there would only be one bloodline left in did that, he would find out where she lived. She his family. Such incidents had happened so called the police nonetheless. To a police officer frequently that the employees never actually he said “We’ll see each other again, and this took them seriously. time it’ll be over notch and bead sights.” When this subject and his exgirlfriend were at a res- Psychological Characteristics taurant where she had paid for his drinks and The two groups differed significantly on the food, he asked her if he could take a shower at variables “feels offended easily” (⌽ϭ.618, her place sometime. She said no and he re- p ϭ .035), “fantasies about revenge after sub- sponded that if she didn’t not want to be his jectively experiencing injustice” (⌽ϭ.500, girlfriend, she would be his enemy. To which p ϭ .031), and “persecutory delusion” (⌽ϭ she replied “Are you trying to threaten me or This document is copyrighted by the American Psychological Association or one of its allied publishers. .786, p ϭ .000; see Table 10). The nonpsychotic shoot me? Then shoot me in the back when I This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. perpetrators felt offended much more easily and cross the street.” He replied “Not in the back,” had more fantasies about revenge. Psychotic whereupon she asked “So you want to look me delusions were mostly persecutory and did not in the eyes?” which he affirmed. She then gave occur, by definition, in the nonpsychotic perpe- him 20 € for gas at his request. trators. Both groups showed leakage behavior: 76.5% of the nonpsychotic (n ϭ 13) and 45.5% Fascination With Violence, Weapons, and of the psychotic individuals (n ϭ 5) without Previous Attempted Homicide significant difference (p ϭ .125). The leakage behavior was shown repeatedly by all five psy- Fascination with violence and weapons was chotic offenders and by 12 nonpsychotic of- found in both groups (see Table 11). Most non- GERMAN MASS MURDERERS AND THEIR WARNING BEHAVIORS 13

Table 10 Psychological Characteristics of Psychotic and Nonpsychotic Offenders

Psychotic Nonpsychotic offenders offenders Psychological characteristics % N % N 10 %80 6 %17 ءFeels offended easily Injustice collector 50% 6 60% 15 15 %60 8 %13 ءFantasies about revenge after subjectively experiencing injustice 18 %0 11 %73 ءءPersecutory delusion Low impulse control 88% 8 61% 18 Self-conscious in social life 40% 10 17% 18 Contact with a criminal milieu 13% 8 44% 16 Denigration of a speciﬁc group of people 57% 7 53% 15 .p Ͻ .001 ءء .p Ͻ .05 ء

psychotic subjects were trained in the use of case files provided almost no information about handguns and rifles (n ϭ 14; 93.3%) which is the past of the offenders. not common in Germany, and nearly one third of psychotic offenders (n ϭ 3; 27.3%) were Critical Life Events and Experiences in adept in the use of firearms as well. The differ- Childhood and Adolescence Until Age 16 ence between groups was significant with a large effect size (⌽ϭ.606, p ϭ .009). The The following findings refer to the first 16 consumption of violent media, such as first- years in the lives of the future perpetrators. person shooter games, and wearing military or Incidents that were labeled as “difficult child- warrior related clothing on a daily basis were hood” were defined by the death of a parent or infrequent in both groups. both parents, the termination of contact with Especially relevant to prevention is the find- one or both parents, being placed into custody ing that 31% of nonpsychotic (n ϭ 4) and 13% or foster care at least once, physical and/or of psychotic offenders (n ϭ 1) had at least tried sexual abuse, and/or substance abuse by one or to kill somebody before their rampage. This both parents or foster parents. Aggregating information was available for 21 cases; nine early negative or traumatic experiences and un-

Table 11 Fascination With Violence and Weapons in Nonpsychotic and Psychotic Offenders

Nonpsychotic Psychotic offenders offenders Afﬁnity towards violence and weapons % N % N Weapons ء

This document is copyrighted by the American Psychological Association or one of its allied publishers. Experienced with using ﬁrearms 93% 15 60% 8 Carries arms in public 21% 19 36% 11 This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. Collector of weapons 42% 19 45% 11 Idealizes weapons 26% 19 18% 11 Leisure time and clothing Leisure time: spends a lot of time consuming violent media 14% 14 13% 8 Leisure time: ﬁrst-person shooter games 7% 15 0% 9 Clothing: wearing black clothes nearly all the time 7% 14 0% 9 Clothing: wearing military, uniform style or militant clothes most of the time 5% 19 0% 9 Clothing: otherwise noticeable clothing 13% 15 0% 8 Former potential deadly violence Tried to kill another individual in the past 31% 13 13% 8 .p Ͻ .05 ء 14 ALLWINN, HOFFMANN, AND MELOY

stable family and broken home situations, it was Institutional Visibility found that nearly half of the nonpsychotic (n ϭ 9, 47.4%) and slightly more than half of the A person was considered institutionally visi- psychotic individuals (n ϭ 6, 54.5%) experi- ble if an institution had reported any kind of enced a difficult childhood. Six nonpsychotic behavior or communication of the future of- perpetrators (31.6%) experienced contact termi- fender that indicated a danger to the self or nation with a parent and five experienced the others, aggressiveness, or behavior regarded as death of one or both parents. Five of the psy- “insane.” Regarding institutional visibility (see chotic offenders experienced contact termina- Table 13), the following categories were con- tion (45.5%) and in one case, one parent died sidered: (a) educational institutions (schools within the first 16 years of the perpetrator’s life. and youth centers); (b) psychological or medi- The two groups did not differ significantly from cal institutions; (c) former or current employers; another (p ϭ .35). Four nonpsychotic perpetra- (d) executive and judicial authorities (police, tors and one psychotic were placed into a foster legal system, military). The mean institutional family or foster home before the age of 16. The visibility ranging from zero to four categories experiences with foster care were statistically for nonpsychotic offenders was 1.47 (SD ϭ similar (p ϭ .32). Parental substance abuse was .772) and 2.09 for psychotic offenders (SD ϭ prevalent in two cases, and both of these future .94); U (19,11) ϭ 142, p ϭ .112. Only one perpetrators became psychotic. One psychotic offender who was nonpsychotic was unknown subject had both parents addicted to drugs. to any institution before the rampage. The visibility to psychological or medical institutions Crises and Stressors Within 1 Year Prior was significantly higher for psychotic perpetra- to the Attack tors (⌽ϭ.451, p ϭ .023). All other categories did not differ significantly between the two The occurrence of crises and stressors within groups. 12 months prior to the violent offenses are shown in Table 12. More than two thirds (n ϭ Summary of Findings 14, 73.7%) of nonpsychotic and 45.5% (n ϭ 5) of psychotic offenders experienced at least one The present study is an explorative and phe- of the following crises or stressors: a rejection nomenological analysis regarding rampage kill- of a desired romantic relationship, dissatisfac- ings and intended killings by adults in Germany tion with the quality of the relationship to a during a time period of 12 years. The adult significant other, social withdrawal, financial killers were mostly male (93.9%). The age difficulties, or disciplinary measures at the range was between 26 and 78 years (M ϭ 46.82, workplace. Rejection of a desired romantic re- SD ϭ 12.68). Nearly half of the perpetrators lationship is the only factor which differed be- were unmarried (45.5%) and lived alone tween groups, and was only relevant for the (54.5%). In most of the cases, they lived in a nonpsychotic individuals (⌽ϭ.468, p ϭ .027). permanent residence (90.9%). Two thirds did

Table 12

This document is copyrighted by the American Psychological Association or one of its allied publishers. Crises and Stressors Within 12 Months Prior to the Attack This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. Nonpsychotic Psychotic offenders offenders Crises and stressors within 12 months % N % N 9 0. 16 43.8 ء(rejection of a desired romantic relationship (N ϭ 25 dissatisfaction with the quality of the relationship to a significant other (N ϭ 16) 50.0 10 16.7 6 social withdrawal (N ϭ 16) 18.2 11 20.0 5 financial difficulties (N ϭ 21) 57.1 14 57.1 7 disciplinary measures at the workplace (N ϭ 24) 7.7 13 10.0 10 At least one of the crises (N ϭ 30) 73.7 19 45.5 11 .p Ͻ .05 ء GERMAN MASS MURDERERS AND THEIR WARNING BEHAVIORS 15

Table 13 deadly violence was noticeable months, years, Institutional Visibility of Nonpsychotic and or even decades earlier in most of the cases, but Psychotic Offenders the specific intent became apparent relatively Nonpsychotic Psychotic late in the pathway toward violence, usually offenders offenders within days or weeks before the killings. In (N ϭ 19) (N ϭ 11) nearly three out of four cases, only one weapon Institution category % n % n was used in the crime, usually firearms. Some- times more than one weapon was carried with- Educational 16% 3 45% 5 -out being used. The perpetrators were in pos ء Psychological-medical 26% 5 73% 8 Work-related 21% 4 18% 2 session of the weapon they would use for years. Executive and judicative 89% 16 64% 7 On average, one person was killed by the mur- Intuitional visibility 95% 19 100% 11 derer and three were wounded. In a third of the p Ͻ .05. cases, no one was killed at the scene despite ء clear intent to do so. In contrast to the crime statistic in Germany for all murders, the victims within our sample are more often without any complete vocational training or university stud- prior relationship to the perpetrator (Adler et al., ies; however, about half (48.5%) did not have a 1993; Bundeskriminalamt, 2018). About half of job at the time of their violent act and had the perpetrators were under the influence of financial difficulties (42.4%). They did not substances during their act, which is a higher reach their occupational goals, and almost half rate compared to other studies (Adler et al., of the killers (30–50%) had no occupational 1993; Gill et al., 2017; Hempel et al., 1999). A education, similar to other studies in Germany suicidal motive was relevant for half of the (Peter & Bogerts, 2012). They often had a crim- sample. inal record (45%, n ϭ 15), frequently more than one offense, and were imprisoned. Only a few Discussion cases had a carefree childhood as far as we know. Tentative appraisal suggests that at least A differential case analysis revealed two half of the perpetrators had a potentially trau- different groups of mass murderers, psychotic matic or desolate childhood and youth. The and nonpsychotic offenders. Deciding spectrum of victims was diverse. It ranged from whether and, if so, how many groups could intimate partners, colleagues at the workplace, reasonably be formed was possible after a to lawyers or medical practitioners. The geog- complete review of all cases. A division into raphy of rampage killings in Germany are psychotic and nonpsychotic individuals was evenly divided between one, and more than one, imposed by the case material. Especially the crime scene in a public space. Half of them violent acts differed clearly. (51.6%) are planned over weeks, months, or Acts by individuals with psychosis were even years. Murderous deeds with less than mostly unplanned and committed with cutting 24-hr lead time (12.9%) or unplanned deeds or stabbing weapons against strangers. The psy- (35.5%) are much less common. In most of the chotic mass murders had contact with mental cases, the subject had a primary or personal health professionals early on, and were known grievance at the beginning. The thoughts to to act suspiciously before their crime. In con- This document is copyrighted by the American Psychological Association or one of its allied publishers. commit a violent act then became funnel-like trast, nonpsychotic individuals planned their This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. and more precise. At the outset of the contin- acts for a long time and used firearms. There- uum, or pathway, was the idea, followed by fore, their crime was more lethal compared to leakage—communication to a third party—and the psychotic offenders, and in line with other then closer to the deed, planning and prepara- German sample studies (Adler et al., 1993). tory behavior (Borum, Fein, Vossekuil, & Ber- In an early study of mass murder by Hempel, glund, 1999). Shortly before the act, perceived Meloy, and Richards (1999), psychotic were grievances and life crises increased signifi- more lethal than nonpsychotic mass murderers. cantly. The specific time, place, and method The reason for our contrasting results may be emerged in many cases without meticulous that in this study the nonpsychotic mass mur- planning. A predisposition to commit an act of derers used firearms, and the individuals with 16 ALLWINN, HOFFMANN, AND MELOY

psychosis generally did not. Firearms pose a Knoll & Meloy, 2014; Meloy et al., 2004). The greater lethality risk than cutting instruments. personal grievance, apparent in this study and The number of civilian firearms per 100 res- most others (Hempel et al., 1999; Silver et al., idents (Small Arms Survey, 2011) is estimated 2018), composed of the elements of loss, hu- to be much higher in the U.S. (n ϭ 89) than in miliation, anger, and blame, becomes fertile soil Germany (n ϭ 30). According to the latest for a perceived injustice which can be added to estimates (Small Arms Survey, 2018), this dif- others, and accumulated over time, often ference (U.S., 120.5; Germany 19.6) has in- months or years. creased even further. Accessibility of firearms Special attention was paid to the perpetrator– increases lethality risk. In the context of severe victim relationship. The victims of the psy- targeted violence by adolescents, most scholars chotic were mostly unknown. Nonpsychotic agree that identification with other perpetrators mass murders, on the other hand, were more or actions plays a special role (Meloy, Mo- likely to attack people they were related to handie, Knoll, & Hoffmann, 2015). However, within a formal or informal relationship. this does not seem to be the case for our sample Among the victims of the nonpsychotic offend- of German adult mass murderers. Identification ers were frequently found former intimate part- with other attackers or assassins, either histori- ners. In line with other studies (e.g., Liem, cal or contemporary, fictional or not, is ex- 2010; Liem & Oberwittler, 2012), this study tremely rare in our sample of adult German also validates a positive correlation between the mass murderers. However, other features of the closeness of the perpetrator’s victim relation- identification warning behavior are observable. ship and the perpetrator’s suicide rate. In addi- The perpetrators show a clear fascination with tion, the personal crises differed between the weapons and militaria and show a striking war- two groups within the last 12 months. Romantic rior mentality (e.g., collect weapons, carry arms rejections were experienced by almost half of in public or idealize weapons). the nonpsychotic offenders, whereas not one Both groups, psychotic and nonpsychotic of- psychotic offender had experienced a romantic fenders, contained high rates of so-called injus- rejection during the year before the act. With a tice collectors. In addition to their fixation on focus on the warning behavior of both groups, perceived injustices, they displayed deadly re- direct death threats in nonpsychotic people were venge fantasies. The aspect of injustice collec- detectable in more than two thirds of the cases, tion is common within adolescent and adult and were significantly more frequently ex- mass murderers (Gill et al., 2017; Mullen, 2004; pressed when compared with their psychotic O’Toole, 2000, 2014, 2015). This study vali- counterparts. In the end, these results validate dates former research of mass shootings regard- the so-called intimacy effect. The intimacy ef- ing the importance of injustice collection, per- fect suggests that the closeness of a relationship ceived as actual events—albeit often magnified correlates with the seriousness of a direct death if not delusional—and incubated in the mind of threat (Jenkins, 2008). Knoll and Hatters- the perpetrator. A retaliatory mentality is not Friedman (2015, p. 1256) summarized the inti- new: For example, the Biblical admonition of macy effect when they wrote “Direct threats are “sow the wind, reap the whirlwind” (Hosea, more likely to predict violence the more inti- 8:7), and the primitive impulse of lex talionis, mate the relationship is.” Our findings show that the law of talion, an eye for an eye. However, even if direct threats of death do not result in an This document is copyrighted by the American Psychological Association or one of its allied publishers. O’Toole described dangerous injustice collec- attack on the target, others may be at risk and This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. tors as follows: [they] “have at least one inci- threat management is very important. For ex- dent in their past when they reacted to a real or ample, a nonpsychotic regularly threatened his perceived injustice in a manner that was (1) exgirlfriend with death, but then killed his cur- disproportionate to the original event and (2) rent partner after the same conflict patterns were aggressive” (O’Toole, 2015, p. 98). repeated. This injustice collection, whether delusional We compared our study with the most recent or not, is often buttressed by a rejection sensi- FBI study of the preincident behaviors of tar- tivity, which in turn is often an aspect of path- geted attackers in the U.S. (Silver et al., 2018). ological narcissism and clinical paranoia that Case selection criteria were different, but com- pervades these cases (Hempel et al., 1999; parisons are noteworthy. Most of the acts were GERMAN MASS MURDERERS AND THEIR WARNING BEHAVIORS 17

planned in advance by both German (64.5%) leakage is much more common. Direct death and U.S. (100%) offenders. The proportion of threats—no matter to whom on the pathway to people with delusional disorders differs signif- violence—are a clear signal that should not be icantly. In the German sample 36.67% (n ϭ 11) ignored. In threat management, it is common were psychotic, whereas the U.S. sample con- sense that the more frequently people express tained only 4.76% (n ϭ 3). However, the two homicidal threats, the greater is the ultimate risk studies applied different criteria to identify de- of serious, targeted violence (Warren, Mullen, lusional disorders. Silver et al. (2018) relied on & McEwan, 2014). Our results underline this official diagnoses by medical or mental health insight. When warning signs occur, threat man- professionals, whereas the present study also agement professionals should start examining included information based on qualitative anal- whether other warning behaviors are present. ysis of the case files by mental health clinicians, As we see, oftentimes more than one warning even if a disorder was never officially diag- behavior is shown. In our sample, more than nosed. More than half of the offenders in both five warning behaviors were shown by psy- studies leaked their intention to harm somebody chotic and more than six by nonpsychotic mass to a third party. German mass murderers show murderers. Although in this study there was no leakage warning behavior in 64% and American comparison group to indicate which warning active shooters in 56% of the cases. Although behaviors can be used as correlates or predictors the recorded stressors differed between the U.S. of violence, other studies have demonstrated and the German study, both groups showed a this relationship (Challacombe & Lucas, 2018; considerable number of stressors within the 12 Meloy et al., 2014, 2019). The most validated months before the attack. Regarding threats, warning behaviors as correlates or predictors of German mass murderers made direct death risk are pathway, identification, and last resort. threats in half of the cases (50%), whereas U.S. Mental health professionals can assess if the active shooters did so in a third of the case person has a mental illness or if he or she is (35%)—but direct threats were more likely in psychotic. Positive symptoms, for example, de- nonpsychotic or relational based targeting in both lusions, can increase the risk of violent behavior studies. All of the U.S. and almost all of the (Douglas, Guy, & Hart, 2009; Witt, Van Dorn, German (96.7%) perpetrators showed conspicu- & Fazel, 2013). The content of the delusion and ous and concerning behavior before their act. potential violent thoughts give important infor- However, the present study evaluated the conspic- mation about the risk. Therefore, teaching of the uous behavior directly visible for institutions. warning behaviors in hospitals and mental Neighbors or acquaintances who had noticed ab- health institutions should be implemented. Per- normalities but had not made this known to an sonal grievances and situational crises are de- institution (e.g., police) were not included. In the tectable and when ameliorated, can help prevent U.S. study, the vast majority of those who noticed a violent act. In addition, the private sphere can concerning behavior talked to the person directly be supported. Family, relatives, and friends, if (Silver et al., 2018), but no one in the U.S. study available, can be informed about the illness, reported leakage to law enforcement. notably about psychotic illnesses and which signals suggest a psychotic phase and how profes- Prevention of Adult Mass Murder sional help can be contacted. The integration of family members with a supportive attitude can This document is copyrighted by the American Psychological Association or one of its allied publishers. Leakage behavior and other warning behav- stabilize the person of concern. Additionally, This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. iors offer the chance for the prevention of tar- the subject can be taught to recognize and clas- geted violence. The intent to commit a violent sify symptoms and signals. Undoubtedly, a act is communicated to third parties, and can trustful relationship between patient and physi- initiate case management. Both psychotic cian, psychiatrist, or psychologist are essential. (45.5%) and nonpsychotic (76.5%) mass mur- The possibility to quickly access firearms, derers showed leakage warning behavior. As such as unsecured firearms in the home, in- mentioned in previous studies (Meloy et al., creases the lethality of a possible attack. This 2012), direct death threats are a warning behav- insight is even more true for psychotic people. ior, and along with leakage warning behavior The analysis of the offenses showed that in the often open a case with the authorities, although case of a psychotic shock, the immediately 18 ALLWINN, HOFFMANN, AND MELOY

available weapon is grabbed. Therefore, stricter Psychotic offenders have been examined gun control laws should be considered (Knoll, closely in this study as they present the largest 2012; Lee, Lee, & Ng, 2007). coherent group among perpetrators with mental Almost every adult German mass murderer illness. Other mental illnesses or psychological raised in advance serious concerns in several conditions have not been taken into consider- institutions, and very often individuals who had ation, although other dynamics associated to been in contact with the offender were deeply mental illness are conceivable and likely. worried. Nonetheless, public services, universi- Therefore, studies with a larger sample and a ties, companies, hospitals, and mental health sufficient amount of data, especially regarding institutions are not always aware of potential the medical history of perpetrators, are called warning signs. Multiple proximal warning be- for. haviors were present in every case. Local threat The dataset is based on the analysis of court assessment networks therefore may be the key files. Qualitative interviews with perpetrators for preventing mass murder. Often adult mass who survived their attacks could contribute to murderers are known in their surroundings and the understanding of the phenomenon. appear early on because of a variety of suspi- In this study, we examined mass murderous cious and noticeable behaviors which produced acts between 2000 and 2012. Considering the concerns. Institutional visibility exists. None- technological advancement in this time span, theless, often the institutions are not connected for example, the development of Social Me- to each other, nor are experts consulted for dia, some behaviors and dynamics may have effective threat management of the case. Net- changed or will change, not only regarding perpetrators but also investigation practices. works between mental health professionals, po- Nonetheless, the authors assume a stability of lice and threat assessment professionals are nec- the overall dynamics and warning behaviors. essary. Collaborations between the health Additionally, such studies can only analyze system and law enforcement are critical, such as behaviors that have become known to the au- the Los Angeles Police Department Threat thorities following investigation. Changes in Management Unit and the Fixated Threat As- threat management practice may produce other sessment Centres in the United Kingdom and results in the future. Australia (Meloy & Hoffmann, 2014). Intended mass murders in the public space are extremely rare and cannot be predicted. In- References stead, persons of concern can be threat managed Adler, L. (2000). Amok [rampage]. Belleville, Ger- if such warning behaviors are apparent. Threat many: Eine Studie. München. assessment and management works to prevent, Adler, L. (2015). Historie und U¨ berblick [History but not predict, targeted violent acts (Meloy, and overview]. In J. Hoffmann & K. Roshdi 2015). Threat assessment and management as (Eds.), Amok und andere Formen schwerer an emerging scientific discipline and an opera- Gewalt. Risikoanalyse—Bedrohungsmanage- tional method can promote the public safety and ment—Präventionskonzepte [Amok and other welfare, while also ensuring help for those who forms of severe violence. Risk analysis-threat management-prevention concepts] (pp. 51–67). pose a danger, often to both themselves and Stuttgart, Germany: Schatthauer. others. Adler, L., Lehmann, K., Räder, K., & Schünemann, This document is copyrighted by the American Psychological Association or one of its allied publishers. K. F. (1993). “Amokläufer”—Kontentanalytische This article is intended solely for the personal use of the individualLimitations user and is not to be disseminated broadly. Untersuchung an 196 Pressemitteilungen aus in- dustrialisierten Ländern [“Running amok” content The current study has no control group and analytical study of 196 press releases from indus- exclusively focuses on cases from Germany. trialized countries]. Fortschritte der Neurologie- For a more comprehensive understanding, com- Psychiatrie, 61, 424–433. http://dx.doi.org/10 paring the results with a control group would be .1055/s-2007-999114 Adler, L., Marx, D., Apel, H., Wolfersdorf, M., & helpful. Hajak, G. (2006). Stability of the “amok runner Weapon availability and weapon laws differ syndrome”. Fortschritte der Neurologie-Psychiat- between countries. This may limit the transfer- rie, 74, 582–590. http://dx.doi.org/10.1055/s- ability of the results. 2005-919092 GERMAN MASS MURDERERS AND THEIR WARNING BEHAVIORS 19

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