Forensic Evidence in Court

Craig Adam is based at the School of Physical and Geographical Sciences, Keele University, Keele, UK. He has been involved in forensic science education and research for almost fifteen years while working at Keele University. Originally a physicist by training, he has particular interests in the mathematical and statistical aspects of the discipline, in addition to his research on the physicochemical characterisation of forensic materials, document analysis and blood dynamics. He has published across all these areas, including the textbook Essential Mathematics and Statistics for Forensic Science, available from Wiley-Blackwell. He has extensive experience in developing teaching resources across the spectrum of forensic science and, over recent years, has focused on the interface between science and the court. This has led him to explore the legal, scientific and statistical perspectives driving the evolution of the crucial step in the progress of scientific evidence from the crime scene through the legal debate to its influence on the ultimate decision by the court.

Preface xvi

Part 1 1

1 An Introduction to the Admissibility of Expert Scientific Opinion 3

1.1 Admissibility, Reliability and Scientific Evidence 3

1.2 The Impact of the DNA Revolution 5

1.3 The Miscarriage of Justice 6

1.3.1 The United Kingdom 7

1.3.2 The United States 8

1.3.3 Canada 8

1.3.4 Australia 9

1.4 DNA Reveals Wrongful Convictions 9

1.5 The Causes of Wrongful Conviction 10

1.6 Unreliable Scientific Evidence 11

1.6.1 The Status and Expertise of the Expert Witness 11

1.6.2 The Expert is not Impartial 12

1.6.3 The Evidence was Wrong 13

1.6.4 Exaggerated Evaluation by the Expert 13

1.6.5 Unethical Behaviour 14

1.6.6 Human Error 14

1.6.7 Non-validated Methodology 15

1.6.8 Overconfidence in New Techniques 15

1.7 The Scientist and the Laboratory 16

1.8 Conclusions 17

References 17

Further Reading 18

2 Admissibility from the Legal Perspective 20

2.1 Admissibility, Relevance and Reliability of Evidence 20

2.2 Admissibility in the United States 22

2.2.1 Reliability and the Frye Test 22

2.2.2 Meeting the Frye Criterion: US v Stifel 1970 23

2.2.3 Admissibility and the Gatekeeper Role: The Daubert Test 23

2.2.4 The Daubert Trilogy 25

2.2.5 General Electric v Joiner 1997 25

2.2.6 Kumo Tire Company v Patrick Carmichael 1999 26

2.2.7 Post]Daubert Hearings: US v Dennis Mooney 2002 26

2.3 Admissibility in Canada 27

2.3.1 R v Mohan 1994 27

2.3.2 R v Abbey 2009 29

2.3.3 R v Trochym 2007 29

2.4 Admissibility in Australia 30

2.4.1 R v Bonython 1984 30

2.4.2 Makita v Sprowles 2001 31

2.4.3 Dasreef Pty Limited v Hawchar 2011 31

2.5 Admissibility in England and Wales 32

2.5.1 R v Turner 1975 33

2.5.2 R v Gilfoyle 2001 33

2.5.3 R v Luttrell 2004 34

2.6 Conclusions on Admissibility 35

2.6.1 Relevance and Expertise 35

2.6.2 The Scientific Basis of the Opinion 35

2.6.3 Weight of Evidence 37

References 37

Further Reading 38

3 Forensic Science and the Law: The Path Forward 39

3.1 National and Legal Developments in the United States 39

3.1.1 Federal Rules of Evidence 40

3.1.2 Strengthening Forensic Science in the United States 2009 41

3.1.3 US Reference Manual on Scientific Evidence 43

3.2 National and Legal Developments in Canada 44

3.2.1 Legal Enquiries into Miscarriages of Justice 44

3.2.2 The Science Manual for Canadian Judges 45

3.3 National and Legal Developments in Australia 46

3.3.1 The Uniform Rules of Evidence 47

3.4 National and Legal Developments in England and Wales 48

3.4.1 Forensic Science on Trial 2005 49

3.4.2 The Law Commission Report 2011 49

3.4.3 The Royal Statistical Society Guides 51

3.4.4 HCSTSC Report Forensic Science 2013 52

3.4.5 UK Government Response (2013) to the Law

Commission Report 52

3.5 Conclusions 53

References 53

Further Reading 54

4 Scientific Opinion and the Law in Practice 56

4.1 Scientific Opinion and the Judicial System 56

4.1.1 Adversarial and Inquisitorial Systems of Justice 56

4.1.2 Scientific Evidence Within the Inquisitorial System 57

4.1.3 Inquisitorial Versus Adversarial 57

4.2 The Scientist in Court 58

4.3 The Role and Duties of the Scientific Expert Witness 59

4.3.1 Definitions of the Role 59

4.3.2 Duties and Responsibilities of the Expert Witness 60

4.4 Quality Control of Analysis and Opinion 61

4.4.1 An Australian Standard for Forensic Analysis 61

4.4.2 Regulation of Forensic Science in the United Kingdom 62

4.4.3 Codes of Conduct and Practice 62

4.4.4 Accreditation of the Expert 63

4.5 Conclusion 63

References 64

Further Reading 64

Part 2 65

5 Fundamentals of the Interpretation and Evaluation of Scientific Evidence 67

5.1 Analysis, Interpretation and Evaluation 67

5.2 The Role and Outcomes of Forensic Investigation 68

5.2.1 Investigative Forensic Science 68

5.2.2 Evaluative Forensic Science 69

5.3 Fact and Opinion 69

5.3.1 Categorisation of Opinions 70

5.3.2 Factual Opinion 70

5.3.3 Investigative Opinion 70

5.4 Expert Opinion and the Forensic Science Paradigm 70

5.4.1 Categorical Opinion 71

5.4.2 Posterior Probabilities 72

5.4.3 Explanations 73

5.4.4 Where Does this Take Us? 74

5.5 What are Propositions? 74

5.5.1 The Hierarchy of Propositions 74

5.5.2 The Importance of Activity Level 75

5.6 Competing Propositions in the Court 76

References 77

Further Reading 77

6 Case Studies in Expert Opinion 78

6.1 Case Study 1: Facial Comparison Evidence 78

6.1.1 The Crime and Conviction 78

6.1.2 Expert Evidence and Opinion 79

6.1.3 Opinion in Atkins 80

6.2 Case Study 2: Ear]mark Identification 81

6.2.1 The Crime and the Evidence 81

6.2.2 Interpreting the Evidence and Challenges to the Opinion 81

6.2.3 The Conclusion of the Appeal 83

6.2.4 Opinion in Dallagher 83

6.3 Case Study 3: Glass and Gunshot Residue 84

6.3.1 The Crime and Trial 84

6.3.2 Analysis and Interpretation of the Scientific Evidence 84

6.3.3 Propositions for Evaluation 85

6.3.4 Evaluative Opinion: Glass 86

6.3.5 Evaluative Opinion: GSR 86

6.3.6 Opinion in Bowden 88

6.4 Conclusions 88

References 88

Further Reading 89

7 Formal Methods for Logical Evaluation 90

7.1 Frequentist and Bayesian Approaches to Evaluation 90

7.1.1 The Frequentist Approach to Formulating Opinion 90

7.1.2 The Logical Evaluation of Evidence 91

7.1.3 The Debate on Formulating Opinion 92

7.2 The Likelihood Ratio Method 92

7.3 Expressing Opinion Through Likelihood Ratio 93

7.3.1 Statements of Evaluative Opinion 93

7.3.2 Likelihood Ratio and Verbal Equivalent Statements 94

7.4 Evaluation and Bayes’ Theorem 94

7.4.1 Bayes’ Theorem: Prior and Posterior Odds 95

7.4.2 Combining Likelihood Ratios 97

7.5 Prior Odds 97

7.6 Posterior Probabilities 99

7.6.1 Opinion and Posterior Probabilities 99

7.6.2 The Prosecutor’s Fallacy 99

7.7 Working Out Conditional Probabilities and Likelihood Ratio 100

7.7.1 Likelihood Ratio at Source Level 100

7.7.2 Likelihood Ratio at Activity Level 101

7.8 Conclusions 102

References 102

Further Reading 103

8 Case Studies in Probabilistic Opinion 104

8.1 People v Collins 1968 104

8.2 R v Michael Shirley 2003 105

8.2.1 A Logical Evaluation of Scientific Evidence 106

8.2.2 The Outcome of the Appeal 108

8.3 R v D J Adams 1996, 1998 108

8.3.1 The Crime and the Evidence 109

8.3.2 A Probabilistic Analysis of the Evidence: Prior Odds 109

8.3.3 The Non]Scientific Evidence 110

8.3.4 The Scientific Evidence 111

8.3.5 Total Likelihood Ratio and Posterior Odds 112

8.3.6 The Appeals 113

8.3.7 Review of the Issues in R v D J Adams 114

8.4 The Defendant’s Fallacy: R v J 2009 115

8.5 Conclusion 116

References 116

Further Reading 116

9 Cognitive Bias and Expert Opinion 117

9.1 Cognitive Bias 117

9.2 Contextual Bias 118

9.2.1 Confirmation Bias 119

9.2.2 Expectation Bias 119

9.2.3 Motivational Bias 119

9.2.4 Anchoring 120

9.3 Other Sources of Bias 120

9.4 Fingerprint Examination: A Case Study in Bias 120

9.4.1 The Review of the Brandon Mayfield Case 2004 120

9.4.2 The Fingerprint Inquiry Scotland 2009 121

9.4.3 Bias Within Fingerprint Examination 121

9.5 Mitigating Bias 122

9.6 Mitigating Bias Versus Research on Traces 123

9.7 Conclusions 124

References 124

Further Reading 125

Part 3 127

10 The Evaluation of DNA Profile Evidence 129

10.1 DNA Profiling Techniques – A Brief History 130

10.2 Databases in DNA Profiling 131

10.2.1 Allele Frequency Databases 131

10.2.2 Identification Databases 131

10.3 Interpretation and Evaluation of Conventional DNA Profiles 131

10.3.1 Combined Probability of Inclusion (CPI) or Exclusion (CPE) 132

10.3.2 Random Match Probability (RMP) 132

10.3.3 Likelihood Ratio 133

10.4 Suspect Identification from a DNA Database 133

10.4.1 The Frequentist Interpretation 133

10.4.2 The Likelihood Ratio Approach 134

10.4.3 Database Search Evidence in Court 134

10.5 Case Studies of DNA in the Court 135

10.5.1 R v Andrew Philip Deen 1994 135

10.5.2 Issues Raised by Expert Opinion in R v Deen 136

10.5.3 R v Alan Doheny 1996 138

10.5.4 The Doheny Trial 138

10.5.5 The Doheny Appeal 139

10.5.6 R v Gary Adams 1996 140

10.5.7 Challenges to the Interpretation of DNA Profiles: US v Shea 1997 141

10.6 Current Practice for Evaluating DNA Profile Evidence 142

10.6.1 The Impact of Doheny and Adams in the United Kingdom 142

10.6.2 Current Practice in the United Kingdom 144

10.6.3 Current Practice in Australia 145

10.7 DNA – The Only Evidence 146

10.8 Errors and Mistakes in Forensic DNA Analysis 147

10.8.1 Adam Scott 2012 147

10.8.2 R v S 2013 148

10.8.3 Laboratory Error Rates Versus the RMP 148

10.9 Conclusions 149

References 149

Further Reading 150

11 Low Template DNA 151

11.1 Technical Issues 151

11.1.1 Terminology 151

11.1.2 Samples 152

11.1.3 Technical Issues in Interpretation 152

11.1.4 Quantitative Evaluation in LTDNA Profiles 153

11.2 Importance of the Chain of Custody: Queen v Sean Hoey 2007 154

11.3 The Caddy Report 2008 155

11.4 Case Studies in LTDNA opinion in the UK Courts 156

11.4.1 Partial Profiles 156

11.4.2 Quantities of DNA; Interpretive Issues on Transfer 157

11.4.3 Very Low Quantities of DNA 159

11.4.4 Opinion Without Statistics 160

11.4.5 Experts Differ in Opinion 162

11.5 LTDNA in Jurisdictions Outside the United Kingdom 163

11.5.1 United States 164

11.5.2 Australia 165

11.6 Conclusions 167

References 167

Further Reading 168

12 Footwear Marks in Court 169

12.1 The Analysis and Interpretation of Footwear Marks 169

12.2 Match Opinion: R v D S Hall 2004 170

12.2.1 The Crime and the Evidence 170

12.2.2 Footwear Mark Evidence and Opinion 171

12.2.3 Review of Expert Opinion in R v Hall 172

12.3 The Likelihood Ratio Approach to Evaluation of Footwear Marks 172

12.4 Standardising Scales for Expert Opinion 173

12.4.1 SWGTREAD Scales of Opinion 173

12.4.2 ENFSI Scales of Opinion 175

12.5 Challenges to Opinion on Footwear Evidence: R v T 2010 175

12.5.1 Outline of the Footwear Mark Evidence in R v T 176

12.5.2 The Expert Witness’ Notes 177

12.5.3 Evaluation Using an Alternative Database 179

12.5.4 The Summary by the Appeal Court Judge 179

12.6 Discussion of R v T 180

12.6.1 Terminology, Probabilities and Statistical Methodology 180

12.6.2 Footwear Databases 181

12.6.3 Was the Jury Told the Basis of the Expert Opinion? 182

12.6.4 The Appeal Court Ruling: Bayes, Mathematics and Formulae 183

12.7 Footwear Mark Evidence After R v T: R v South 2011 184

12.7.1 The Crime and Evidence 184

12.7.2 Evaluation of the Footwear Evidence 184

12.7.3 Review of the Expert Opinion 185

12.8 ENFSI Recommendations on Logical Evaluation 2015 186

12.9 Conclusions 187

References 187

Further Reading 188

13 Fingerprints and Finger]Marks – Identifying Individuals? 189

13.1 Fingerprint Identification on Trial 189

13.2 ACE]V: A Scientific Method? 190

13.3 Evaluation Criteria 191

13.3.1 Thresholds for Categorical Evaluation 191

13.3.2 The Balthazard Model 192

13.3.3 Identification Thresholds and the Points Standard in the United Kingdom 192

13.3.4 The Basis of the Non]Numeric (Holistic) Approach 193

13.3.5 Identification Thresholds in Other Jurisdictions 194

13.3.6 R v Buckley 1999 194

13.4 Evolution of the Basis of Fingerprint Opinion in the Court 196

13.5 A Critical Summary of Fingerprint Identification 198

13.6 Challenges to Fingerprint Testimony 198

13.6.1 R v P K Smith 2011 198

13.6.2 Shirley McKie and the Scottish Fingerprint Inquiry 1997–2011 200

13.7 Identifying a Mark from a Database 202

13.7.1 AFIS Versus Manual Systems 202

13.7.2 The Madrid Bombing Case (Brandon Mayfield) 2004 203

13.8 Admissibility of Fingerprint Evidence 204

13.8.1 US v Byron Mitchell 2004 204

13.8.2 US v Llera Plaza 2002 205

13.9 Towards a Probabilistic Evaluation of Fingerprint Evidence 206

13.10 Conclusions 208

References 208

Further Reading 209

14 Trace Evidence, Databases and Evaluation 210

14.1 Analytical Methodologies for Glass, Fibres and GSR 210

14.1.1 Glass Analysis 211

14.1.2 Fibre Analysis 211

14.1.3 GSR Analysis 211

14.2 Databases for Source and Activity Levels 212

14.2.1 Source Level 212

14.2.2 Activity Level 212

14.2.3 Glass 213

14.2.4 Fibres 213

14.2.5 GSR 213

14.2.6 Statistical Models and Case Pre]Assessment 214

14.3 Glass Evidence in Court 214

14.3.1 R v Abadom 1983 214

14.3.2 R v Lewis]Barnes 2014 215

14.3.3 R v L and Others 2010 216

14.3.4 People v Smith 2012 216

14.3.5 Review of the Evaluation of Trace Glass Evidence 217

14.4 Fibre Evidence in Court: R v Dobson 2011, R v Norris 2013 218

14.4.1 Fibre Evidence: Dobson 219

14.4.2 Fibre Evidence: Norris 220

14.4.3 Review of the Evaluation of the Fibre Evidence 221

14.5 Gunshot Residue (GSR) Evidence in Court 222

14.5.1 R v Wooton and Others 2012 222

14.5.2 R v Gjikokaj 2014 224

14.5.3 Review of the Evaluation of GSR Evidence 225

14.5.4 R v George 2007 226

14.6 Conclusions 227

References 227

Further Reading 227

15 Firearm and Tool]Mark Evidence 229

15.1 Pattern Matching of Mechanical Damage 229

15.2 The Interpretation and Evaluation of Tool]Mark Evidence 230

15.2.1 US Opinion 230

15.2.2 UK Opinion 232

15.3 Critical Review of Tool]Mark Evaluation 232

15.4 Consecutive Matching Striations 234

15.5 Databases 234

15.6 Tool]Marks and Evaluation by Likelihood Ratio 235

15.7 Firearms Evidence in the US Courts 236

15.7.1 United States v Hicks 2004 236

15.7.2 United States v Darryl Green et al. 2005 237

15.7.3 US v Glynn 2008 240

15.8 Concluding Comments on Firearms Cases 241

References 241

Further Reading 242

16 Expert Opinion and Evidence of Human Identity 243

16.1 Introduction to Ear]Marks 243

16.2 R v Kempster 2003, 2008 244

16.2.1 The First Appeal 2003 245

16.2.2 The Second Appeal 2008 245

16.2.3 Conclusions From R v Kempster 246

16.3 State v Kunze 1999 247

16.3.1 The Frye Hearing 247

16.3.2 The Trial 248

16.3.3 The Appeal 249

16.4 Review of Ear]Mark Cases 249

16.5 Introduction to Bite]Mark Evidence 250

16.6 The ABFO Guidelines and Expert Opinion 250

16.7 Bite]Mark Cases in the United States 251

16.7.1 People v Marx 1975 252

16.7.2 The Appeal 252

16.7.3 State v Garrison 1978 253

16.7.4 State v Stinson 1986 254

16.7.5 Bite]Mark Testimony in the Courts 255

16.8 Body Biometrics: Facial Mapping and Gait 255

16.8.1 R v Hookway 1999 255

16.8.2 R v Otway 2011 256

16.9 Conclusion 257

References 257

Further Reading 258

17 Questioned Documents 259

17.1 Handwriting and Signature Comparison – A Scientific Methodology? 260

17.2 Scales of Expert Opinion 261

17.3 Jarrold v Isajul and Others 2013 263

17.3.1 Dr Strach’s Testimony 264

17.3.2 Mr Holland’s Testimony 264

17.3.3 Mr Lacroix’s Testimony 265

17.3.4 The Appeal Court Judge’s Conclusion 265

17.4 Gale v Gale 2010 266

17.4.1 ESDA Analysis 267

17.4.2 Signature Analysis 267

17.5 The Bridgewater Four (R v Hickey and Others) 1997 268

17.5.1 Molloy’s ‘Confession’ 269

17.6 R v Previte 2005 270

17.7 Admissibility and Other Issues in Handwriting and Signature Evidence 271

17.8 Admissibility and Evaluation in the US Courts 272

17.8.1 US v Starzecpyzel 1995 272

17.8.2 US v Velasquez 1995 274

17.9 Conclusions 275

References 275

Further Reading 276

18 Bloodstain Pattern Analysis 277

18.1 The Nature of Bloodstain Pattern Evidence 277

18.2 Issues for BPA Expert Opinion in the Courts 278

18.2.1 The Scientific Basis of BPA 278

18.2.2 Who is the Expert? 279

18.2.3 The Courts’ and Lawyers’ Knowledge of BPA 280

18.2.4 The Evaluation and Significance of BPA Evidence 280

18.3 The Scientific Basis of Bloodstain Pattern Analysis: The Murder of Marilyn Sheppard 281

18.4 Three Approaches to the Presentation of Blood Evidence 282

18.4.1 Activity and Propositions: R v Thompson 2013 283

18.4.2 No Expert Testimony: R v White 1998 283

18.4.3 Reconstructing Activity as a Narrative: R v Hall 2010 284

18.5 The Problem of Expirated Blood 285

18.5.1 R v O’Grady 1995, 1999 286

18.5.2 R v Jenkins: The Trial and First Appeal 1999 287

18.5.3 R v Jenkins: The Second Appeal (2004) and

Two More Retrials 289

18.6 Experts in Disagreement: R v Perlett 2006 289

18.7 Conclusions 291

References 291

Further Reading 292

19 Conflicting Expert Opinion: SIDS and the Medical Expert Witness 293

19.1 Eminent Experts: Issues and Conflicts 293

19.2 R v Clark 2000, 2003 294

19.2.1 The Testimony of Meadow 295

19.2.2 The Second Appeal 2003 297

19.3 A Bayesian Analysis: Murder or SIDS? 298

19.3.1 Pr(H2) – The Probability of Two SIDS Deaths in the Same Family 298

19.3.2 Pr(H1) – The Probability of Two Murdered Infants in the Same Family 299

19.3.3 The Posterior Odds 299

19.4 R v Cannings 2004 300

19.5 Trupti Patel 2003 302

19.5.1 The Rib Fracture Evidence 302

19.5.2 The Judge’s Summing Up 303

19.6 Conclusions 304

References 304

Further Reading 305

Appendix: Some Legal Terminology 306

Index of Cases, Individuals and Inquiry Reports 307

General Index 309