Alma Mater Studiorum – Università di Bologna In collaborazione con LAST-JD consortium: Università degli studi di Torino Universitat Autonoma de Barcelona Mykolas Romeris University Tilburg University DOTTORATO DI RICERCA IN Erasmus Mundus Joint International Doctoral Degree in Law, Science and Technology Ciclo 29 – A.Y. 2013/2014 Settore Concorsuale di afferenza: 12H3 Settore Scientifico disciplinare: IUS20 TITOLO TESI Knowledge Production from Social Network Sites - Using Social Media Evidence in the Criminal Procedure _______________________________ Presentata da: Chih-Ping Chang Coordinatore Relatore Prof. Giovanni Sartor Prof. Dr. Alberto Artosi CIRSFID, University of Bologna, Italy Co- Relatore Prof. Dr. Giovanni Ziccardi University of Milan, Italy Esame finale anno 2018 Alma Mater Studiorum – Università di Bologna in partnership with LAST-JD Consoritum Università degli studi di Torino Universitat Autonoma de Barcelona Mykolas Romeris University Tilburg University PhD Programme in Erasmus Mundus Joint International Doctoral Degree in Law, Science and Technology Cycle 29 – a.y. 2013/14 Settore Concorsuale di afferenza: 12H3 Settore Scientifico disciplinare: IUS20 (Title of the Thesis) Knowledge Production from Social Network Sites - Using Social Media Evidence in the Criminal Procedure Submitted by: Chih-Ping Chang The PhD Programme Coordinator Supervisor (s) Prof. Giovanni Sartor Prof. Dr. Alberto Artosi CIRSFID, University of Bologna, Italy Prof. Dr. Giovanni Ziccardi University of Milan, Italy Year 2018 Abstract This thesis focuses on the interaction between social network sites (SNS) and the legal system, trying to answer a specific question, that is, through introducing social media evidence, whether there is a change of finding facts and identifying the truth in criminal proceedings. To achieve the research objectives, three sub-topics should be discussed in turn; first, how can we transform information on social network sites to valuable evidence in court? In this part, the research will explore the proceedings of extracting information on SNS, such as posts, photos, check-in on Facebook etc., in order to use as evidence in the courtroom from the perspectives of law and internet forensic. Second, considering characteristics of these social media evidence, e.g. easy to be copied, deleted, tampered and transmitted, is it necessary to separate from evidence obtained through other technology or forensic science? Should the legal system need a new set of regulation on social media evidence? Third, how can we conquer challenges to core values in legal system, such as the privilege against self-incrimination or expectation of innocent in this digital era? As the positive contribution, this research tries to answer whether social network sites are a convenient tool for criminal prosecution, and whether internet forensics is useful to assist the investigational authority accusing the crime and finding the truth more accurately, to achieve the ultimate goal of the criminal procedure? Table of Contents INTRODUCTION ...................................................................................................... ‐ 11 ‐ RESEARCH MOTIVATIONS ............................................................................................ ‐ 11 ‐ 1. A START FROM A SIMPLE CASE, WHICH MIGHT HAPPEN DAILY ............................ - 11 - 2. PRIVACY CRISIS? ........................................................................................................ - 14 - 3. INTERACTIONS BETWEEN THE LAW AND SCIENCE ................................................... - 19 - 3.1 Negligence in Forensic Process ................................................................................. ‐ 20 ‐ 3.2 Paradigm Shift and New Objectivity ........................................................................ ‐ 23 ‐ RESEARCH QUESTIONS ................................................................................................ ‐ 27 ‐ METHODOLOGY ........................................................................................................... ‐ 29 ‐ STRUCTURE OF THIS THESIS ........................................................................................ ‐ 31 ‐ CHAPTER 1 SOCIAL MEDIA EVIDENCE ............................................................. ‐ 38 ‐ 1. DEFINITION ................................................................................................................. - 38 - 1.1 Social Network Sites .................................................................................................. ‐ 39 ‐ 1.1.1 Structure of Social Network Sites ........................................................................... ‐ 41 ‐ 1.1.2 Characteristics ......................................................................................................... ‐ 42 ‐ 1.2 Social Media .............................................................................................................. ‐ 44 ‐ 1.3 Social Media Evidence ............................................................................................... ‐ 45 ‐ 2. TYPES AND FORMATS OF SOCIAL MEDIA EVIDENCE ................................................ - 46 - 3. ACQUISITIONS (HOW TO GET IT?) ............................................................................ - 47 - 3.1 Computer Forensics ................................................................................................... ‐ 48 ‐ 3.2 Digital Forensics ........................................................................................................ ‐ 48 ‐ 3.3 Network/ Internet Forensics ....................................................................................... ‐ 49 ‐ 4. TYPES OF EVIDENCE IN LEGAL SYSTEMS ................................................................. - 50 - 4.1 Digital Evidence ......................................................................................................... ‐ 51 ‐ 4.2 Scientific Evidence .................................................................................................... ‐ 52 ‐ 4.3 Social Media Evidence ............................................................................................... ‐ 54 ‐ 5. OTHER SIMILAR CHARACTERISTICS WITH DIGITAL EVIDENCE ............................. - 54 - 5.1 Vulnerable to Tampering ............................................................................................ ‐ 55 ‐ 5.2 Possible to Recovery .................................................................................................. ‐ 55 ‐ 5.3 Unlimited to Copy ...................................................................................................... ‐ 56 ‐ 5.4 Hard to Identify .......................................................................................................... ‐ 57 ‐ 5.5 Cannot directly to Sense or Understand by Human ................................................... ‐ 58 ‐ ‐ 1 ‐ 5.6 Difficult to Collect ..................................................................................................... ‐ 59 ‐ 5.7 Dependence on the Environment ............................................................................... ‐ 59 ‐ 6. SUMMARY .................................................................................................................... - 60 - CHAPTER 2 SOCIAL MEDIA EVIDENCE IN CRIMINAL PROCEDURE ........... ‐ 64 ‐ SECTION 1 DIFFERENCE BETWEEN TAIWAN AND AMERICAN LEGAL SYSTEM .............. ‐ 64 ‐ 1. RULE OF EVIDENCE IN AMERICA ............................................................................... - 65 - 2. RULE OF EVIDENCE IN TAIWAN ................................................................................. - 66 - SECTION 2 AMERICAN LAW .......................................................................................... ‐ 67 ‐ 3. DISCOVERABILITY OF EVIDENCE .............................................................................. - 70 - 3.1 Rules for Search and Seizure ..................................................................................... ‐ 72 ‐ 3.1.1 The Standard: Reasonable Expectation of Privacy ................................................. ‐ 72 ‐ 3.1.2 Operation Rules of Search on Social Network Sites ............................................... ‐ 73 ‐ 3.2 Obtain Evidence from Public Domain ....................................................................... ‐ 76 ‐ 3.3 Search with a Warrant ................................................................................................ ‐ 78 ‐ 3.3.1 Probable Cause ........................................................................................................ ‐ 78 ‐ 3.3.2 Requirement of Particularity ................................................................................... ‐ 79 ‐ 3.4 Exceptions for the Search without Warrant ................................................................ ‐ 82 ‐ 3.4.1 Search with Subject’s Consent ................................................................................ ‐ 82 ‐ 3.4.1.1 Consent ................................................................................................................. ‐ 83 ‐ 3.4.1.2 Scope of Consent ................................................................................................. ‐ 84 ‐ 3.4.1.3 The Third Party Consent ...................................................................................... ‐ 85 ‐ 3.4.2 Exigent Circumstances ...........................................................................................