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 xviPart 1 11 An Introduction to the Admissibility of Expert Scientific Opinion 31.1 Admissibility, Reliability and Scientific Evidence 31.2 The Impact of the DNA Revolution 51.3 The Miscarriage of Justice 61.3.1 The United Kingdom 71.3.2 The United States 81.3.3 Canada 81.3.4 Australia 91.4 DNA Reveals Wrongful Convictions 91.5 The Causes of Wrongful Conviction 101.6 Unreliable Scientific Evidence 111.6.1 The Status and Expertise of the Expert Witness 111.6.2 The Expert is not Impartial 121.6.3 The Evidence was Wrong 131.6.4 Exaggerated Evaluation by the Expert 131.6.5 Unethical Behaviour 141.6.6 Human Error 141.6.7 Non-validated Methodology 151.6.8 Overconfidence in New Techniques 151.7 The Scientist and the Laboratory 161.8 Conclusions 17References 17Further Reading 182 Admissibility from the Legal Perspective 202.1 Admissibility, Relevance and Reliability of Evidence 202.2 Admissibility in the United States 222.2.1 Reliability and the Frye Test 222.2.2 Meeting the Frye Criterion: US v Stifel 1970 232.2.3 Admissibility and the Gatekeeper Role: The Daubert Test 232.2.4 The Daubert Trilogy 252.2.5 General Electric v Joiner 1997 252.2.6 Kumo Tire Company v Patrick Carmichael 1999 262.2.7 Post]Daubert Hearings: US v Dennis Mooney 2002 262.3 Admissibility in Canada 272.3.1 R v Mohan 1994 272.3.2 R v Abbey 2009 292.3.3 R v Trochym 2007 292.4 Admissibility in Australia 302.4.1 R v Bonython 1984 302.4.2 Makita v Sprowles 2001 312.4.3 Dasreef Pty Limited v Hawchar 2011 312.5 Admissibility in England and Wales 322.5.1 R v Turner 1975 332.5.2 R v Gilfoyle 2001 332.5.3 R v Luttrell 2004 342.6 Conclusions on Admissibility 352.6.1 Relevance and Expertise 352.6.2 The Scientific Basis of the Opinion 352.6.3 Weight of Evidence 37References 37Further Reading 383 Forensic Science and the Law: The Path Forward 393.1 National and Legal Developments in the United States 393.1.1 Federal Rules of Evidence 403.1.2 Strengthening Forensic Science in the United States 2009 413.1.3 US Reference Manual on Scientific Evidence 433.2 National and Legal Developments in Canada 443.2.1 Legal Enquiries into Miscarriages of Justice 443.2.2 The Science Manual for Canadian Judges 453.3 National and Legal Developments in Australia 463.3.1 The Uniform Rules of Evidence 473.4 National and Legal Developments in England and Wales 483.4.1 Forensic Science on Trial 2005 493.4.2 The Law Commission Report 2011 493.4.3 The Royal Statistical Society Guides 513.4.4 HCSTSC Report Forensic Science 2013 523.4.5 UK Government Response (2013) to the LawCommission Report 523.5 Conclusions 53References 53Further Reading 544 Scientific Opinion and the Law in Practice 564.1 Scientific Opinion and the Judicial System 564.1.1 Adversarial and Inquisitorial Systems of Justice 564.1.2 Scientific Evidence Within the Inquisitorial System 574.1.3 Inquisitorial Versus Adversarial 574.2 The Scientist in Court 584.3 The Role and Duties of the Scientific Expert Witness 594.3.1 Definitions of the Role 594.3.2 Duties and Responsibilities of the Expert Witness 604.4 Quality Control of Analysis and Opinion 614.4.1 An Australian Standard for Forensic Analysis 614.4.2 Regulation of Forensic Science in the United Kingdom 624.4.3 Codes of Conduct and Practice 624.4.4 Accreditation of the Expert 634.5 Conclusion 63References 64Further Reading 64Part 2 655 Fundamentals of the Interpretation and Evaluation of Scientific Evidence 675.1 Analysis, Interpretation and Evaluation 675.2 The Role and Outcomes of Forensic Investigation 685.2.1 Investigative Forensic Science 685.2.2 Evaluative Forensic Science 695.3 Fact and Opinion 695.3.1 Categorisation of Opinions 705.3.2 Factual Opinion 705.3.3 Investigative Opinion 705.4 Expert Opinion and the Forensic Science Paradigm 705.4.1 Categorical Opinion 715.4.2 Posterior Probabilities 725.4.3 Explanations 735.4.4 Where Does this Take Us? 745.5 What are Propositions? 745.5.1 The Hierarchy of Propositions 745.5.2 The Importance of Activity Level 755.6 Competing Propositions in the Court 76References 77Further Reading 776 Case Studies in Expert Opinion 786.1 Case Study 1: Facial Comparison Evidence 786.1.1 The Crime and Conviction 786.1.2 Expert Evidence and Opinion 796.1.3 Opinion in Atkins 806.2 Case Study 2: Ear]mark Identification 816.2.1 The Crime and the Evidence 816.2.2 Interpreting the Evidence and Challenges to the Opinion 816.2.3 The Conclusion of the Appeal 836.2.4 Opinion in Dallagher 836.3 Case Study 3: Glass and Gunshot Residue 846.3.1 The Crime and Trial 846.3.2 Analysis and Interpretation of the Scientific Evidence 846.3.3 Propositions for Evaluation 856.3.4 Evaluative Opinion: Glass 866.3.5 Evaluative Opinion: GSR 866.3.6 Opinion in Bowden 886.4 Conclusions 88References 88Further Reading 897 Formal Methods for Logical Evaluation 907.1 Frequentist and Bayesian Approaches to Evaluation 907.1.1 The Frequentist Approach to Formulating Opinion 907.1.2 The Logical Evaluation of Evidence 917.1.3 The Debate on Formulating Opinion 927.2 The Likelihood Ratio Method 927.3 Expressing Opinion Through Likelihood Ratio 937.3.1 Statements of Evaluative Opinion 937.3.2 Likelihood Ratio and Verbal Equivalent Statements 947.4 Evaluation and Bayes’ Theorem 947.4.1 Bayes’ Theorem: Prior and Posterior Odds 957.4.2 Combining Likelihood Ratios 977.5 Prior Odds 977.6 Posterior Probabilities 997.6.1 Opinion and Posterior Probabilities 997.6.2 The Prosecutor’s Fallacy 997.7 Working Out Conditional Probabilities and Likelihood Ratio 1007.7.1 Likelihood Ratio at Source Level 1007.7.2 Likelihood Ratio at Activity Level 1017.8 Conclusions 102References 102Further Reading 1038 Case Studies in Probabilistic Opinion 1048.1 People v Collins 1968 1048.2 R v Michael Shirley 2003 1058.2.1 A Logical Evaluation of Scientific Evidence 1068.2.2 The Outcome of the Appeal 1088.3 R v D J Adams 1996, 1998 1088.3.1 The Crime and the Evidence 1098.3.2 A Probabilistic Analysis of the Evidence: Prior Odds 1098.3.3 The Non]Scientific Evidence 1108.3.4 The Scientific Evidence 1118.3.5 Total Likelihood Ratio and Posterior Odds 1128.3.6 The Appeals 1138.3.7 Review of the Issues in R v D J Adams 1148.4 The Defendant’s Fallacy: R v J 2009 1158.5 Conclusion 116References 116Further Reading 1169 Cognitive Bias and Expert Opinion 1179.1 Cognitive Bias 1179.2 Contextual Bias 1189.2.1 Confirmation Bias 1199.2.2 Expectation Bias 1199.2.3 Motivational Bias 1199.2.4 Anchoring 1209.3 Other Sources of Bias 1209.4 Fingerprint Examination: A Case Study in Bias 1209.4.1 The Review of the Brandon Mayfield Case 2004 1209.4.2 The Fingerprint Inquiry Scotland 2009 1219.4.3 Bias Within Fingerprint Examination 1219.5 Mitigating Bias 1229.6 Mitigating Bias Versus Research on Traces 1239.7 Conclusions 124References 124Further Reading 125Part 3 12710 The Evaluation of DNA Profile Evidence 12910.1 DNA Profiling Techniques – A Brief History 13010.2 Databases in DNA Profiling 13110.2.1 Allele Frequency Databases 13110.2.2 Identification Databases 13110.3 Interpretation and Evaluation of Conventional DNA Profiles 13110.3.1 Combined Probability of Inclusion (CPI) or Exclusion (CPE) 13210.3.2 Random Match Probability (RMP) 13210.3.3 Likelihood Ratio 13310.4 Suspect Identification from a DNA Database 13310.4.1 The Frequentist Interpretation 13310.4.2 The Likelihood Ratio Approach 13410.4.3 Database Search Evidence in Court 13410.5 Case Studies of DNA in the Court 13510.5.1 R v Andrew Philip Deen 1994 13510.5.2 Issues Raised by Expert Opinion in R v Deen 13610.5.3 R v Alan Doheny 1996 13810.5.4 The Doheny Trial 13810.5.5 The Doheny Appeal 13910.5.6 R v Gary Adams 1996 14010.5.7 Challenges to the Interpretation of DNA Profiles: US v Shea 1997 14110.6 Current Practice for Evaluating DNA Profile Evidence 14210.6.1 The Impact of Doheny and Adams in the United Kingdom 14210.6.2 Current Practice in the United Kingdom 14410.6.3 Current Practice in Australia 14510.7 DNA – The Only Evidence 14610.8 Errors and Mistakes in Forensic DNA Analysis 14710.8.1 Adam Scott 2012 14710.8.2 R v S 2013 14810.8.3 Laboratory Error Rates Versus the RMP 14810.9 Conclusions 149References 149Further Reading 15011 Low Template DNA 15111.1 Technical Issues 15111.1.1 Terminology 15111.1.2 Samples 15211.1.3 Technical Issues in Interpretation 15211.1.4 Quantitative Evaluation in LTDNA Profiles 15311.2 Importance of the Chain of Custody: Queen v Sean Hoey 2007 15411.3 The Caddy Report 2008 15511.4 Case Studies in LTDNA opinion in the UK Courts 15611.4.1 Partial Profiles 15611.4.2 Quantities of DNA; Interpretive Issues on Transfer 15711.4.3 Very Low Quantities of DNA 15911.4.4 Opinion Without Statistics 16011.4.5 Experts Differ in Opinion 16211.5 LTDNA in Jurisdictions Outside the United Kingdom 16311.5.1 United States 16411.5.2 Australia 16511.6 Conclusions 167References 167Further Reading 16812 Footwear Marks in Court 16912.1 The Analysis and Interpretation of Footwear Marks 16912.2 Match Opinion: R v D S Hall 2004 17012.2.1 The Crime and the Evidence 17012.2.2 Footwear Mark Evidence and Opinion 17112.2.3 Review of Expert Opinion in R v Hall 17212.3 The Likelihood Ratio Approach to Evaluation of Footwear Marks 17212.4 Standardising Scales for Expert Opinion 17312.4.1 SWGTREAD Scales of Opinion 17312.4.2 ENFSI Scales of Opinion 17512.5 Challenges to Opinion on Footwear Evidence: R v T 2010 17512.5.1 Outline of the Footwear Mark Evidence in R v T 17612.5.2 The Expert Witness’ Notes 17712.5.3 Evaluation Using an Alternative Database 17912.5.4 The Summary by the Appeal Court Judge 17912.6 Discussion of R v T 18012.6.1 Terminology, Probabilities and Statistical Methodology 18012.6.2 Footwear Databases 18112.6.3 Was the Jury Told the Basis of the Expert Opinion? 18212.6.4 The Appeal Court Ruling: Bayes, Mathematics and Formulae 18312.7 Footwear Mark Evidence After R v T: R v South 2011 18412.7.1 The Crime and Evidence 18412.7.2 Evaluation of the Footwear Evidence 18412.7.3 Review of the Expert Opinion 18512.8 ENFSI Recommendations on Logical Evaluation 2015 18612.9 Conclusions 187References 187Further Reading 18813 Fingerprints and Finger]Marks – Identifying Individuals? 18913.1 Fingerprint Identification on Trial 18913.2 ACE]V: A Scientific Method? 19013.3 Evaluation Criteria 19113.3.1 Thresholds for Categorical Evaluation 19113.3.2 The Balthazard Model 19213.3.3 Identification Thresholds and the Points Standard in the United Kingdom 19213.3.4 The Basis of the Non]Numeric (Holistic) Approach 19313.3.5 Identification Thresholds in Other Jurisdictions 19413.3.6 R v Buckley 1999 19413.4 Evolution of the Basis of Fingerprint Opinion in the Court 19613.5 A Critical Summary of Fingerprint Identification 19813.6 Challenges to Fingerprint Testimony 19813.6.1 R v P K Smith 2011 19813.6.2 Shirley McKie and the Scottish Fingerprint Inquiry 1997–2011 20013.7 Identifying a Mark from a Database 20213.7.1 AFIS Versus Manual Systems 20213.7.2 The Madrid Bombing Case (Brandon Mayfield) 2004 20313.8 Admissibility of Fingerprint Evidence 20413.8.1 US v Byron Mitchell 2004 20413.8.2 US v Llera Plaza 2002 20513.9 Towards a Probabilistic Evaluation of Fingerprint Evidence 20613.10 Conclusions 208References 208Further Reading 20914 Trace Evidence, Databases and Evaluation 21014.1 Analytical Methodologies for Glass, Fibres and GSR 21014.1.1 Glass Analysis 21114.1.2 Fibre Analysis 21114.1.3 GSR Analysis 21114.2 Databases for Source and Activity Levels 21214.2.1 Source Level 21214.2.2 Activity Level 21214.2.3 Glass 21314.2.4 Fibres 21314.2.5 GSR 21314.2.6 Statistical Models and Case Pre]Assessment 21414.3 Glass Evidence in Court 21414.3.1 R v Abadom 1983 21414.3.2 R v Lewis]Barnes 2014 21514.3.3 R v L and Others 2010 21614.3.4 People v Smith 2012 21614.3.5 Review of the Evaluation of Trace Glass Evidence 21714.4 Fibre Evidence in Court: R v Dobson 2011, R v Norris 2013 21814.4.1 Fibre Evidence: Dobson 21914.4.2 Fibre Evidence: Norris 22014.4.3 Review of the Evaluation of the Fibre Evidence 22114.5 Gunshot Residue (GSR) Evidence in Court 22214.5.1 R v Wooton and Others 2012 22214.5.2 R v Gjikokaj 2014 22414.5.3 Review of the Evaluation of GSR Evidence 22514.5.4 R v George 2007 22614.6 Conclusions 227References 227Further Reading 22715 Firearm and Tool]Mark Evidence 22915.1 Pattern Matching of Mechanical Damage 22915.2 The Interpretation and Evaluation of Tool]Mark Evidence 23015.2.1 US Opinion 23015.2.2 UK Opinion 23215.3 Critical Review of Tool]Mark Evaluation 23215.4 Consecutive Matching Striations 23415.5 Databases 23415.6 Tool]Marks and Evaluation by Likelihood Ratio 23515.7 Firearms Evidence in the US Courts 23615.7.1 United States v Hicks 2004 23615.7.2 United States v Darryl Green et al. 2005 23715.7.3 US v Glynn 2008 24015.8 Concluding Comments on Firearms Cases 241References 241Further Reading 24216 Expert Opinion and Evidence of Human Identity 24316.1 Introduction to Ear]Marks 24316.2 R v Kempster 2003, 2008 24416.2.1 The First Appeal 2003 24516.2.2 The Second Appeal 2008 24516.2.3 Conclusions From R v Kempster 24616.3 State v Kunze 1999 24716.3.1 The Frye Hearing 24716.3.2 The Trial 24816.3.3 The Appeal 24916.4 Review of Ear]Mark Cases 24916.5 Introduction to Bite]Mark Evidence 25016.6 The ABFO Guidelines and Expert Opinion 25016.7 Bite]Mark Cases in the United States 25116.7.1 People v Marx 1975 25216.7.2 The Appeal 25216.7.3 State v Garrison 1978 25316.7.4 State v Stinson 1986 25416.7.5 Bite]Mark Testimony in the Courts 25516.8 Body Biometrics: Facial Mapping and Gait 25516.8.1 R v Hookway 1999 25516.8.2 R v Otway 2011 25616.9 Conclusion 257References 257Further Reading 25817 Questioned Documents 25917.1 Handwriting and Signature Comparison – A Scientific Methodology? 26017.2 Scales of Expert Opinion 26117.3 Jarrold v Isajul and Others 2013 26317.3.1 Dr Strach’s Testimony 26417.3.2 Mr Holland’s Testimony 26417.3.3 Mr Lacroix’s Testimony 26517.3.4 The Appeal Court Judge’s Conclusion 26517.4 Gale v Gale 2010 26617.4.1 ESDA Analysis 26717.4.2 Signature Analysis 26717.5 The Bridgewater Four (R v Hickey and Others) 1997 26817.5.1 Molloy’s ‘Confession’ 26917.6 R v Previte 2005 27017.7 Admissibility and Other Issues in Handwriting and Signature Evidence 27117.8 Admissibility and Evaluation in the US Courts 27217.8.1 US v Starzecpyzel 1995 27217.8.2 US v Velasquez 1995 27417.9 Conclusions 275References 275Further Reading 27618 Bloodstain Pattern Analysis 27718.1 The Nature of Bloodstain Pattern Evidence 27718.2 Issues for BPA Expert Opinion in the Courts 27818.2.1 The Scientific Basis of BPA 27818.2.2 Who is the Expert? 27918.2.3 The Courts’ and Lawyers’ Knowledge of BPA 28018.2.4 The Evaluation and Significance of BPA Evidence 28018.3 The Scientific Basis of Bloodstain Pattern Analysis: The Murder of Marilyn Sheppard 28118.4 Three Approaches to the Presentation of Blood Evidence 28218.4.1 Activity and Propositions: R v Thompson 2013 28318.4.2 No Expert Testimony: R v White 1998 28318.4.3 Reconstructing Activity as a Narrative: R v Hall 2010 28418.5 The Problem of Expirated Blood 28518.5.1 R v O’Grady 1995, 1999 28618.5.2 R v Jenkins: The Trial and First Appeal 1999 28718.5.3 R v Jenkins: The Second Appeal (2004) andTwo More Retrials 28918.6 Experts in Disagreement: R v Perlett 2006 28918.7 Conclusions 291References 291Further Reading 29219 Conflicting Expert Opinion: SIDS and the Medical Expert Witness 29319.1 Eminent Experts: Issues and Conflicts 29319.2 R v Clark 2000, 2003 29419.2.1 The Testimony of Meadow 29519.2.2 The Second Appeal 2003 29719.3 A Bayesian Analysis: Murder or SIDS? 29819.3.1 Pr(H2) – The Probability of Two SIDS Deaths in the Same Family 29819.3.2 Pr(H1) – The Probability of Two Murdered Infants in the Same Family 29919.3.3 The Posterior Odds 29919.4 R v Cannings 2004 30019.5 Trupti Patel 2003 30219.5.1 The Rib Fracture Evidence 30219.5.2 The Judge’s Summing Up 30319.6 Conclusions 304References 304Further Reading 305Appendix: Some Legal Terminology 306Index of Cases, Individuals and Inquiry Reports 307General Index 309