The forensic challenge

• Author: Paul Roberts
• Pages: 43-66

FRONTIERS OF LAW IN CHINA

VOL. 13 MARCH 2018 NO. 1

DOI 10.3868/s050-007-018-0005-4

FOCUS

COMPARATIVE PERSPECTIVES ON EVIDENCE LAW : EAST AND WEST

THE FORENSIC CHALLENGE

Paul Roberts*

Abstract This article investigates what might be characterised as “the forensic

challenge” for criminal adjudication and clarifies its nature and scope. The “challenge”

identified is complex, dynamic and multifaceted, encompassing a variety of issues and

debates concerning the ways in which forensic science evidence is validated, generated,

presented, tested, evaluated and utilised in criminal proceedings. Common law

evidentiary principles governing the admissibility of scientific evidence and expert

witness testimony are reviewed and the underlying assumptions and potential

weaknesses of adversarial trial procedure are critically considered. The discussion is

pitched at the generic level of recurring intellectual puzzles, institutional design,

regulatory frameworks, procedural structures and processes, macro-policy choices and

methodological prescriptions, with the intention of making it relevant to an international

audience. Aspects of the procedural law and adjudicative practice of England and Wales,

and the regulatory context of UK forensic science, are offered as concrete illustrations

with the potential for illuminating comparative extrapolation to other legal systems. In

conclusion, the article draws out specific implications for Chinese scholarship, law

reform and policymaking in relation to scientific and other expert evidence, and

advances a bold suggestion for entertaining an unconventionally expansive conception

of “forensic science” and, correspondingly, of the challenges it presents.

Keywords forensic science, expert evidence, criminal procedure, comparative legal

method, criminal justice reform

I. CONFRONTING FORENSIC COMPLEXITY ............................................................................. 44

II. COMPARATIVE DIAGNOSTICS ............................................................................................ 48

* Paul Roberts, BCL, MA (Oxford), MPhil (Cambridge), UK; Professor of Criminal Jurisprudence,

University of Nottingham, Nottingham NG7 2RD, UK; Adjunct Professor of Law, Collaborative Innovation

Centre of Judicial Civilization, China University of Political Science and Law, Beijing 100088, China.

Contact: Paul.Roberts@nottingham.ac.uk

I am grateful to two journal referees for helpful feedback, and to the organisers of the VIth International

Conference on Evidence Law and Forensic Science (ICFIS), Baltimore, USA, Aug. 14–16, 2017, for inviting

me to make the keynote presentation on which this article is based.

44 FRONTIERS OF LAW IN CHINA [Vol. 13: 43

III. REGULATING EXPERT EVIDENCE ..................................................................................... 56

IV. ADDRESSING THE CHALLENGE: METHODOLOGICAL PRESCRIPTIONS .............................. 61

I. CONFRONTING FORENSIC COMPLEXITY

Two forensic science-related stories appeared in the UK national media during the

week I began writing this article. The first story concerned the publication of semi-official

scientific “primers” to assist lawyers and courts to understand, interpret and apply certain

kinds of evidence derived from commonly utilised forensic techniques.1 The first two

primers in the series explain “forensic DNA analysis” and “forensic gait analysis,” with

the next tranche planned to address statistics and the physics of vehicle collisions.2 The

second national media story reported “[t]housands of criminal cases under review” owing

to the possibility that “forensic lab results may have been manipulated.”3 This latest

public scandal concerned drug tests undertaken by a private company instructed by the

police, potentially affecting some 10,000 criminal cases, including homicides, sexual and

violent offences. These two stories vividly evoke what we might characterise as “the

forensic challenge” for legislators, policymakers and the routine administration of

criminal justice. This challenge is complex and multifaceted. For one thing, the culturally

resonant “CSI effect”4 entails that forensic science is always newsworthy and seldom out

of the news. For another, forensic science has a Jekyll and Hyde popular persona.

Sometimes the news about forensic science is good news, reporting breakthrough

scientific progress or notable successes in investigations or prosecutions. But just as often

1 Pallab Ghosh, UK Judges to Get Scientific Guides, BBC News, Nov. 22, 2017, available at

http://www.bbc.co.uk/news/science-environment-42057009 (last visited Nov. 30, 2017); Courtroom Science

Primers Launched Today, Royal Society Press Release, available at https://royalsociety.org/news/2017/11/

royal-society-launches-courtroom-science-primers (last visited Nov. 24, 2017). One of the project’s directors,

Professor Sue Black, was interviewed on BBC Radio 4’s flagship Today programme on Nov. 22, 2017,

available at http://www.bbc.co.uk/programmes/b09fj9jk (last visited Nov. 30, 2017). The primers, though

strictly speaking unofficial guidance, are endorsed by the senior judiciary. Also see David Neuberger, Stop

Needless Dispute of Science in the Courts, 531 Nature 9, 9 (2016).

2 The primers are available at https://royalsociety.org/about-us/programmes/science-and-law (last visited

Nov. 30, 2017).

3 Hannah Devlin & Vikram Dodd, Thousands of Criminal Cases under Review, The Guardian, Nov. 22,

2017; Martin Evans, Forensics Lab Tests Tampering Probe Identifies 10,000 Criminal Cases that Might

Have Been Affected, The Telegraph, Nov. 21, 2017; Lizzie Dearden, Convictions in Doubt as More than

10,000 Cases Could be Affected by Data Manipulation at Forensics Lab — Scandal has caused drug driving

cases to be dropped and deaths referred to the Court of Appeal, The Independent, Nov. 21, 2017.

4 Christopher Lawless, Forensic Science: A Sociological Introduction, Routledge, at chapter 2 (2016);

Andrew P. Thomas, The CSI Effect and its Real-Life Impact on Justice: A Study by the Maricopa County

Attorney’s Office, 39 Prosecutor, 10 (2005); N. J. Schweitzer and Michael J. Saks, The CSI Effect: Popular

Fiction about Forensic Science Affects the Public’s Expectations about Real Forensic Science, 47 Jurimetrics

Journal, 357 (2007).