Handbook of Forensic Science

Jim Fraser, Robin Williams

• Publisher: Willan
• Year: 2013
• Print ISBN: 9781843923114
• eBook ISBN: 9781134028702
• Topic: Law
• Subtopic: Forensic Science
• Index: Law

Forensic science has become increasingly important within contemporary criminal justice, from criminal investigation through to courtroom deliberations, and an increasing number of agencies and individuals are having to engage with its contribution to contemporary justice.

This Handbook aims to provide an authoritative map of the landscape of forensic science within the criminal justice system of the UK. It sets out the essential features of the subject, covering the disciplinary, technological, organizational and legislative resources that are brought together to make up contemporary forensic science practice.

It is the first full-length publication which reviews forensic science in a wider political, economic, social, technological and legal context, identifying emerging themes on the current status and potential future of forensic science as part of the criminal justice system. With contributions from many of the leading authorities in the field it will be essential reading for both students and practitioners.

Chapter 1

The contemporary landscape of forensic science

Jim Fraser and Robin Williams

Introduction

Physical evidence cannot be wrong, it cannot perjure itself, it cannot be wholly absent. Only human failure to find it, study and understand it, can diminish its value.

(Kirk: 1974)

Some place their faith in forensic science to the degree that they are under the impression that it is absolute, infallible and unassailable. In truth it is a manmade construct, dependent on manmade machinery, man-calibrated accuracy, man-led action under manmade protocols and analyzed by man – an altogether human construct.

(American Academy of Forensic Sciences cited in Pyrek (2007: 2)

Forensic science plainly has something of value to offer to criminal investigators and the courts. Why, then, does so much of it cling, instead, to an untenable absolutism and committed subjectivity?

(Saks 1998: 1090)

Differing understandings of the nature of forensic science and of the value of its contribution to criminal justice, like those captured in the varying claims quoted above, are found throughout the many celebratory and critical commentaries that articulate its contemporary condition and future promise. There is general agreement amongst the majority of observers that technical progress in a number of forensic science disciplines, along with growing police and judicial confidence in the robustness of their analyses, facilitates an increasing and exceptional contribution to criminal investigations and prosecutions in advanced industrial societies.¹ For some scholars and practitioners, this phenomenon needs no special explanation, being simply one of the ways in which seemingly objective scientific discoveries are increasingly brought to bear on rational decision-making and collective actions in such societies. For others, including many of those involved in the profession of forensic science itself, a more cautious attitude may be discerned. Underlying such caution is the observation of the (under-appreciated) heterogeneity of forensic science practice, along with the persistent absence of agreement on how best to determine and formulate any underpinning commonality of ambition, reasoning or practice amongst its constituent elements.² Despite the efforts of writers like Inman and Rudin (2001) to develop statements of common principles and practice, and notwithstanding notable generic advances (for example in the deployment of Bayesian reasoning) as well as developments in individual forensic disciplines (for example in DNA profiling), there remain significant conceptual and empirical dissonances that hamper efforts to arrive at a shared understanding of many of the most basic features of the forensic endeavour.³ In addition, the multiplicity of ways in which forensic science is applied to individual cases, and the heterogeneity that inevitably follows variation in legal procedures in different jurisdictions, act as further barriers to the widespread standardisation of forensic science knowledge and practice.

This chapter is no more than an initial foray into this complex discursive and practical terrain; terrain that subsequently will be navigated in much more detail by the many distinguished contributors to this Handbook. Accordingly, the next few pages are limited to a sketch of the overall intellectual, legal, organisational and policy contexts in which we locate the several sections and many chapters that make up the book as a whole. In this introduction then, we merely make visible the factors we have sought to consider in our own efforts to analyse and understand the condition and role of forensic science in contemporary criminal justice processes. These considerations include: the theoretical underpinnings of forensic science in general, and of specific advances in particular; the developing operational uses of a range of forensic technologies to support investigations; the authority accorded to forensic expertise by criminal justice actors in particular and by wider publics in general; the underlying, and often tense relationship between the epistemic idioms of science and the law; and the interplay of state, public and commercial interests in the expansion and regulation of forensic science and its criminal justice applications. We attempt a transnational perspective on the many issues under consideration since, although some are specific to UK jurisdictions, we believe such developments are of interest and relevance to other jurisdictions given the increasing internationalisation of crime and policing, the avowedly universal character of scientific knowledge, and the increasing rate of knowledge transfer across national boundaries.

We begin by acknowledging the many terminological complexities that arise in efforts to characterise the predominant features of this field of theory and practice. Such complexities are immediately obvious with regard to the underlying notion of ‘science’ and the scope of its application to a bewildering variety of disciplines and investigative processes. In fact, even the conventional use of the singular noun in the term ‘forensic science’ can work to conceal the multiplicity of scientific disciplines that claim a place in this domain as well as differences in the ways in which they are applied in varying forensic contexts.⁴ Despite these uncomfortable facts, however, the use of the plural form ‘forensic sciences’ remains rare and will hardly be found in the pages of this Handbook. Terminologically, it can also be argued that there are many occasions when the expressions ‘forensic technology’ or ‘forensic technologies’ should be preferred to that of ‘forensic science’, since usually what is described is not a body of theoretical knowledge, but rather the practical application of one or several bodies of knowledge, albeit through disciplined human procedures and the use of a variety of instruments and tools. Throughout this text we assume that references to ‘technology’ will remind readers of the fact that specific forensic innovations cannot be understood without reference to the social desires and strategies that occasioned their development (even where – as is the case with DNA profiling, for example – the original impetus may have come from outside the field of criminal investigation).⁵

Indeed, it is worth noting that the term ‘forensic science’ is one that is most associated with the Anglophone world, or perhaps the common law jurisdictions typical of that world. The term is much less common in continental Europe and has no direct equivalent in a number of European languages. In Germany the word ‘kriminalistik’ was coined to represent the activities of applied forensic investigators, and has been widely taken up in the USA (in the terms ‘criminalistics’ and ‘criminalist’) and in some European countries to describe a certain subset of forensic activities, although it is still sometimes used synonymously with ‘forensic science’ (see Houck and Siegal 2006). In Finland, the nearest equivalent is ‘technical crime investigation’, recognising that whatever this set of activities contains, they are subsets of investigation that engage technological means rather than subsets of science. Indeed it is possible to argue that careful evaluation of the numerous roles and activities sometimes included under the heading of forensic science practice may establish that many of these are only loosely related to formal principles of scientific knowledge and practice (see Fraser 2007b).

Many other difficulties and differences arise in the effort to capture, even on a preliminary basis, the constitutive features of forensic science.⁶ For this reason, when commissioning contributions to this Handbook, we have worked with a deliberately inclusive understanding of the distinctiveness of forensic science as a collection of expert practices whose ambition is to draw on a body of universally valid scientific knowledge, apply reliable technologies and robust methodologies to individual cases, and link underlying principles to localised practical reasoning in support of the goals of criminal justice. Thus, whilst forensic science is concerned with the exploration, explication and evaluation of fundamental facts such as the identity, origin and life history of materials, substances and artefacts by scientific methodologies and technologies, its approach to the discovery and interpretation of all such local instances of these facts is necessarily conditioned by the requirement to provide disciplined conclusions that are both relevant to practical investigative decisions and also recognised by legitimate judicial authority. The authors of the chapters that follow this introduction do not necessarily share our perspective on all of these matters (indeed some may disagree with our comments or our emphases), but we hope that this initial overview of an extensive and varied field of applied systematic practice will usefully orientate readers who go on to read what our colleagues have written in the body of the Handbook.

Mapping forensic science

Strong positive images of the authority of contemporary forensic science are everywhere. They provide a resource for governmental actors concerned to show their commitment to increasingly effective crime control, they frame the technological commodities and services offered to such actors by both public sector and commercial providers, and they are the stuff of endless factual and fictional media representations.⁷

For example, in an account of what seems an instance of an unusually effective government programme, the Forensic Science and Pathology Unit of the UK Home Office (2005a) state that the presence of forensic evidence, more specifically DNA, increases the likelihood of detection of dwelling-house burglaries by almost threefold (from 16 per cent to 41 per cent). However, the significance of this claim as an account of the effectiveness of DNA collection and analysis is not universally accepted and the causal relationship between the presence of forensic evidence and the successful detection of an offence (let alone the successful prosecution of an offender) remains little explored and largely unexplained. A recent US report (Roman et al. 2008) provides the first substantive large-scale study of the effectiveness and cost effectiveness of DNA in volume crime, and this work did show that property offences in which DNA was discovered at the crime scene and subsequently analysed had twice as many suspects arrested (and more than twice as many cases accepted for prosecution) as those that did not. However, the use of a randomised control trial methodology in this study has yet to be followed in any other study of the use of forensic science in support of criminal investigations.

Despite this general shortcoming, the availability of forensic science evidence in individual cases of serious crime can often be shown to have had especially dramatic effects. An example of such cases was also included in the UK Home Office publication mentioned above. In this instance, two young girls (aged eleven and nine) were raped and indecently assaulted in Canterbury, Kent in 1988. Whilst the perpetrator was not identified at the time, 13 years later and over 175 miles away in Derby, a shoplifter was arrested and his DNA sample taken. The resulting profile was automatically uploaded to the National DNA Database of England and Wales (NDNAD) and was found to match the 1988 crime scene samples. On arrest, the suspect admitted his guilt, was speedily tried and sentenced to a term in jail. Such an example can – and invariably is – used to illustrate, in powerful and emotive terms, the impact of DNA technology and its use as an inceptive tool for the investigation of crime. Without the availability of crime scene and subject genetic samples, there would have been little or no prospect of an arrest let alone a prosecution or conviction in this, and many other similar cases. In addition, the guilty plea by this particular suspect confirms the overwhelming authority of the DNA in the absence of virtually any other substantive evidence. Such instances do much to foster the impression that forensic evidence has no boundaries or limitations to its application, being able to reach back almost indefinitely in time in this and other cases.⁸

In turn, such positive investigative outcomes have prompted the retrospective systematic review of many historic controversial cases (for example those of James Hanratty, Stephen Downing, and others)⁹ as well as the resolution of significant miscarriages of justice, such as the case of those convicted in 1990 of the murder of Lynette White, a young prostitute, who was murdered in 1988. In this case, and two years later, the Court of Appeal overturned the conviction of the ‘Cardiff Three’ and questioned the reliability of the interview and confession evidence presented at the original trial. Following a series of unsuccessful reviews of the case, a final review found small specks of blood on a cellophane wrapper from a condom and the key ring of the flat, which were insufficient for analysis in 1988 (and which had also been overlooked in previous reviews). A complete reassessment of the crime scene by a behavioural scientist and the forensic scientist working together, and reenactment of the incident, led to reconsideration of recovered fingermarks and retained materials such as some sections of wallpaper. DNA profiles obtained from these materials eliminated all previous suspects including the ‘Cardiff Three’, but did not match any profile then held on the NDNAD. In 2002, the relatively novel technique of ‘familial searching’ the NDNAD, on this occasion based on the presence of a rare allele found in the crime scene profile, resulted in a request for a voluntary intelligence sample from Jeffrey Gafoor, a local security guard whose relative was on the database and with whom he shared a ‘familial’ pattern. After providing the confirmatory buccal sample, Jeffrey Gafoor unsuccessfully attempted suicide, and in July 2003 he pleaded guilty to the murder – 15 years after the crime.

However, despite the appeal of these, and other such affirmative accounts, there exist many less optimistic understandings of the nature of forensic science in general, its relationship with the law, and the effectiveness of its deployment in efforts to detect crime and prosecute offenders.¹⁰ Jurists, policymakers and a variety of critics have constantly revisited the claims of forensic science to ‘speak truth to justice’, the former sometimes encountering the difficulty of translating from legal to scientific...

Table of contents

• Cover Page
• Half Title Page
• Title Page
• Copyright Page
• Contents
• List of figures and tables
• List of abbreviations
• Acknowledgements
• Notes on contributors
• Preface
• 1 The contemporary landscape of forensic science
• Part 1 Forensic Science Practice
• Section 1: Identifying individuals
• 2 The current status of DNA profiling in the UK
• 3 Fingerprints
• 4 Forensic anthropology and human identification from the skeleton
• Section 2: Identifying and comparing materials
• 5 Drugs of abuse
• 6 Body fluids in sexual offences
• 7 Trace evidence
• 8 Marks
• Section 3 Reconstructing events
• 9 Bloodstain pattern analysis
• 10 Fire investigation policies and practices in the UK
• Part 2 Forensic Science as Investigative Support
• 11 Forensic resources and criminal investigations
• 12 DNA databases
• 13 Using forensic science in major crime inquiries
• 14 Forensic science in UK policing Strategies, Tactics And Effectiveness
• Part 3 Forensic Reasoning and the Evaluation of Scientific Evidence
• 15 Statistics and forensic science
• 16 Understanding forensic science opinions
• 17 The science of proof forensic science evidence in English criminal trials
• Part 4 Themes and Debates in Contemporary Forensic Science
• 18 Forensic science and the internationalisation of policing
• 19 Forensic science, ethics and criminal justice
• 20 Professional standards, public protection and the administration of justice
• 21 The development and enhancement of forensic expertise Higher Education And In-Service Training
• 22 The future(s) of forensic investigations
• Glossary
• Index