Evolution of DNA Evidence Use in the Legal System

Introduction

Who could have imagined, when DNA was first identified as the genetic material half a century ago, that DNA analysis would by now have come to play so large a role in the criminal justice system, and in the public perception of the law? Even twenty years ago, forensic scientists could tell only whether a blood sample was animal or human, male or female, and, if human, of what type.[1]

The criminal Justice system as it is today, is arguably heavily reliant on forensic evidence and with Alec Jeffreys’ discovery of Genetic Profiling in 1984 it has since become increasingly dependent on DNA evidence for the most serious crimes. Its application since its inception has seen a drastic rise, for both its investigatory purpose and consequently within the courtroom for its evidentiary value. DNA Profiling is an extremely formidable forensic tool, with the power to both exonerate and convict individuals.

As a consequence, this evidence requires the respect of all parties involved in the legal process for justice, or risk an over acceptance and reliance on DNA evidence at trial from jurors. A jury’s tendency to convict maybe swayed by individual jurors’ pre-held conceptions, in the presence of, or lack thereof DNA evidence. These misconceptions are sometimes formed from, consciously or subconsciously, the media’s portrayal of DNA evidence, this effect often being coined the “CSI Effect”.[2] Therefore, forensic experts must be able to convey this complex form of evidence to the jury in the most appropriate manner, while lawyers and judges guide them with suitable direction on the evidence so that they may have a comprehensive understanding in order to reach an informed decision on such evidence and its value.

The focus of this dissertation will be to discuss the development of DNA evidence as a forensic tool in the criminal justice system, concentrating on how the different parties that make up that system receive such evidence and the safeguards that currently exists to combat overreliance on what is widely considered to be an infallible form of evidence.

Chapter one will concentrate on the use of DNA evidence within the legal system, highlighting the legal scientific relationship, the development of DNA Profiling as a forensic tool and its admissibility. An understanding of these points is a necessity in order to fully appreciate why there is such a belief in the reliability of this evidence and consequently why its use is relied upon worldwide.

The second chapter shall be examining the evaluation, presentation and interpretation of DNA Evidence. To carry out this analysis a consideration of how difficult it is to interpret such a unique form of evidence is required and therefore the essential nature of such evidence to be accurately presented to the court, as well as an appreciation of the weight that lay individuals may attach. DNA evidence is one of the few forms of evidence that is expressed as a largely numerical statistic, and unrestricted presentation has the potential for miscarriages of justice.

Chapter three will take note of the traditional safeguards and the concerns within an adversarial trial, this will require an in-depth look at the current and potential safeguards, as well as the necessity for their implementation.

Chapter 1: DNA Evidence and the Criminal Justice System

The Legal Scientific Relationship

Scientifically rigorous, but accessible forensic science matters to the criminal justice system as a whole, which is the “customer” for forensic evidence. It matters to you, the members of the criminal bar, who rely on expert evidence whether representing the defence or prosecution, to represent properly your client. It matters to the judiciary in ensuring fairness of proceedings, directing the jury, and upholding the rule of law. And it matters to society more generally, in ensuring that the innocent are not convicted of crimes they did not commit and that the perpetrators of serious crimes are brought to justice.[3]

Science and law, these are two disciplines that have arguably the most profound and meaningful effect on an individual’s life, nearly everything in society is primarily dictated by these embodiments of truth and justice.[9]

It is these conflicts upon which scientific values clash with the adversarial system. The law requires finality in its decisions based on available evidence, it doesn’t have time to wait for perfection.[13]

However, with the allure of developments and advancements in technology and science, it is unsurprising that science would find a permanent home amongst the courtrooms.[17] Therefore, the scope and demand for techniques such as DNA analysis are increasing drastically, encouraged by an aspiration to meet the high demands of the legal doctrine “beyond all reasonable doubt” and the new more infallible forms of evidence required by the criminal courts.

‘It would be entirely wrong to deny to the law of evidence the advantages to be gained from new techniques and new advances in science’.[26] Consideration will be given to some of these initiatives and others through-out the proceeding chapters with a focus towards DNA evidence.

The Development of DNA Profiling as a Tool

Since its inception DNA profiling has become an indispensable tool in the fight against major crime. It has the potential to provide unambiguous identification of individuals from trace amounts of organic material left at crime scenes and the acquittal of the innocent.[30] In order to fully understand the importance of DNA analysis for human identification, some knowledge of the discovery and development of Genetic Profiling is required.

The idea of Genetic Profiling or DNA Fingerprinting[32]

In March 1985, Jeffreys’ technique was first used in an immigration case[36]

Not long after its use in immigration cases Jeffreys’ team developed their technique further producing what they termed Genetic Profiling for application as a forensic tool, and in 1986 their technique was used to exonerate Richard Buckland[39] was born.

Admissibility of DNA Evidence

Expert Opinion Evidence

The general rule for witness evidence is that evidence of opinion is inadmissible. Although, when it comes to expert witnesses, exceptions have been made by both statute and common law. Unlike some jurisdictions,[45]

The principal motivation behind the Law Commission’s report was that expert evidence was being admitted to readily and prone to little scrutiny; expert evidence, as it was for Ms Clark,[50] Codification would have worked to provide a surer basis for the admissibility of expert evidence and it has been recognised that the lack of codification falls short of the standard that would be achieved through an admissibility test enshrined in statute. The amendments that were made to the Rules and Practise Directions will nonetheless go some way towards diminishing the danger of miscarriages of justice from unobstructed, unsuitable, or defective expert evidence.

In the absence of codification, the common law remains the main source of guidelines for the admissibility and weight of expert evidence. As such expert opinion evidence is generally considered to be admissible at common law where: it is relevant to a matter in issue; it provides the court with information which is likely outside the judge’s or jury’s knowledge and expertise; the expert is competent to give the opinion.[54]

R v Ward[64]

Nonetheless, despite the aforementioned challenges surrounding the admission of expert evidence, DNA evidence is here to stay and there is little that could rise to the challenge of its display. Instead, the focus must be on mitigating issues with, for instance, the interpretation and presentation of DNA evidence.

Deepening Complexity and Further Developments

As with many other fields of forensic evidence, new and more sophisticated techniques are being developed to meet the challenges set by the courts. Arguably one of the most controversial is LCN analysis. This profiling technique allows experts to analyse samples that contain only trace amounts of DNA; samples containing less than 100pg.[69]

It is important that as these new techniques develop, they should go through sufficient scientific rigour, so that criminal justice practitioners and experts may be content with the reliability of such methods as LCN to be used as evidentiary tools. This concern was raised by Mr Justice Weir in R v Sean Hoey;[75]

Chapter 2: The Interpretation, Presentation, and Evaluation

Dealing with DNA Evidence

The most fundamental question imposed on DNA evidence is how best to interpret and present its value at trial. The allure of DNA evidence is its capability of being presented almost exclusively in the form of numerical statistics; it allows the “certainty” of a match to be quantified.[77]

This chapter will, therefore, examine the differing means by which DNA evidence may be analysed and effectively quantified and the effect of such quantification on jurors, who often lack statistical backgrounds.[78]

Principles

When a DNA sample is first assessed two propositions are typically formulated. The prosecution proposition; the DNA recovered from the crime scene comes from the accused (Hp), and the defence proposition; the DNA comes from another individual (Hd1). With the defence routinely incorporating the additional proposition that the DNA was not from a close blood relative (Hd2),[80] An effective analysis of the probative value of DNA evidence can only take place with reference to these competing propositions. As reasoned by Evett and Weir:

1. To evaluate the uncertainty of any given proposition it is necessary to consider at least one alternative proposition.

2. Scientific interpretation is based on questions of the kind “What is the probability of the evidence given the proposition?”

3. Scientific interpretation is conditioned not only by the competing propositions, but also by the framework of circumstances within which they are to be evaluated.[81]

A failure to adhere these three principals of interpretation have often led to serious errors and misconceptions such as the “Prosecution’s Fallacy”.[82]

Likelihood Ratios

A likelihood ratio (LR) provides for the strength of evidence to be measured through the comparison of two probabilities conditioned on a pair of alternative assumptions.[83] For DNA evidence a likelihood ratio is obtained when the probability (Pr) that the DNA profile matches the accused (E), given the prosecution’s proposition (Hp) being true, is divided by the probabilitythat the DNA profile matches the accused, given that the defence’s proposition (Hd) is assumed to be true.

LR = Pr(E|Hp)[85]

Take for example that Pr(E|Hp) = 1 and Pr(E|Hd) = 1/1000

Thus the Likelihood Ratio will equal 1/0.001 = 1000

The evidence is, therefore, a thousand times more likely on the prosecution’s hypothesis, as compared to the defence hypothesis.

When the likelihood ratio is greater than one it provides support for the prosecution’s hypothesis. Smaller than one and support is provided for the defence’s proposition, and a ratio equal to one demonstrates that the evidence has no relevance and thus inadmissible.[87] It is an assessment of the two hypotheses for the same assertion; the DNA source matches the defendant, given differing conditions, whether the defendant is guilty or innocent.

Bayes’ Theorem

Bayes’ theorem[88] allows for the assessment of other evidence against statistical and scientific evidence. The theorem provides the means to revise and update our beliefs in light of new evidence. The updated belief consists of our prior belief multiplied by the likelihood ratio:

Posterior odds = Prior odds x LR

Prior odds represent the view formed by the jury prior to the admission of DNA evidence and may be based on other evidence (Oe) adduced that cannot be numerically quantified but rather forms the juries’ opinion of fact.

Prior odds = Pr(Hp|Oe) ÷ Pr(Hd|Oe)

Posterior odds represent the juries view after the admission of DNA evidence.

Posterior odds = Pr(Hp|E,Oe) ÷ Pr(Hd|E,Oe)

Therefore: Pr(Hp|E,Oe) ÷ Pr(Hd|E,Oe) = (Pr(Hp|Oe) ÷ Pr(Hd|Oe)) x (Pr(E|Hp,Oe) ÷  Pr(E|Hd,Oe))

The assessment of different types of evidence about a hypothesis and the effect this has on our updated beliefs is essential to legal proceedings. Bayes’ theorem is simply a formalisation of this type of reasoning. Despite this, the use of Bayes’ theorem has largely been rejected by the courts.[89]

Convicted on statistics

Misrepresentation, Misinterpretation, and Fallacious reasoning

I should, I think, members of the jury just sound a word of caution about the statistics. However compelling you may find them to be, we do not convict people in these courts on statistics. It would be a terrible day if that were so.[90]

Misrepresentation of the data, either by expert witness or lawyers, and miscarriages of justice occur when errors in logic are made. This may arise when the probability of DNA evidence under a particular hypothesis is inappropriately confused with the probability of the hypothesis given the evidence. Such an error in logic is colloquially known as the “Prosecutor’s Fallacy”[92] A way of conceptualising this error is a consideration of the following:

(A) If you are reading this dissertation, you can read English.

(B) If you can read English, you are reading this dissertation.

In this way, it is easy to see that these are not in fact equivalent. One is clearly true the other patently false. This is an error of the transposed conditional; proposition (B) is not a natural progression of proposition (A). For parties of the criminal justice system to treat these propositions as equal is to propagate an error in logic. It is a confusion of the probability of the evidence assuming the defendant’s innocence (I), Pr(E|I), and the probability of their innocence assuming the evidence, Pr(I|E). However, as shown by the above conceptualization these are not equivalent: Pr(E|I) ≠ Pr(I|E) or Pr(A|B) ≠ Pr(B|A).[93]

A very real example of this fallacy[103]

Source Probability

This is the most common example of the prosecutor’s fallacy.[109]

(Q) Is it possible that the semen could have come from a different person from the person who provided the blood sample?

(A) It is possible but it is so unlikely as to really not be credible. I can calculate; I can estimate the chances of this semen having come from a man other than the provider of the blood sample. I can work out the chances as being less than 1 in 27 million.[110]

A similar fallacious statement was made in the trial of Doheny,[112] the unfortunate distortion of the statistics may not have occurred.

Although experts carry a portion of the blame for these types of errors they are usually made with the assistance of lawyers in lines of questioning such as that in Adams[114]

Probability of innocence

This concern with source probability has the potential to extend so as to comment on the probability of whether the defendant is guilty of the crime for which they are accused.[117]

Defence Attorney’s Fallacy

Although this error in logic favours the defendant and as a consequence is less concerning when it comes to miscarriages of justice, it is still worth noting in order to highlight the different ways in which DNA evidence may be misinterpreted. In the preliminary hearings in the case of thePeople v Simpson,[119]

The promotion of the prosecutor’s fallacy formed the main reasoning behind why the appeal in R v Deen[125] Despite this Adams was found guilty both at his original trial and subsequent retrial.

Evidence at Trial

Likelihood Ratios and Verbal Equivalents

Due to perceived issues that come with assessing likelihood ratios, they are now routinely expressed using verbal equivalents. Put simply, forensic scientists have developed a scale to translate likelihood ratios into a verbal description; they are believed to better convey the probative value of evidence to jurors. This has encouraged such organisations as the Association of Forensic Science Providers[126] to endorse such scales, and has been employed by some scientists of the Forensic Science Service. An example of such a scale can be found below:

Likelihood ratio Numerical expression		Likelihood ratio verbal equivalent (support)
Prosecution Hypothesis	Defence Hypothesis
1	1	Inconclusive
1 to 10	1 to 0.1	Weak or limited
10 to 100	0.1 to 0.01	Moderately supports
100 to 1000	0.01 to 0.001	Strongly supports
1,000 to 1,000,000	0.001 to 0.000001	Very strong
Greater than 1,000,000	Greater than 0.000001	Extremely strong

Decisions of the Court of Appeal have demonstrated their recognition of verbal descriptions for non-quantifiable evidence, based on the expert’s own experience, in fields of forensics that require significant subjective interpretation.[132]

The reasoning behind the Court of Appeal’s decision in R v Dlugosz[139]

The true significance of an expert’s inability to use a hierarchy of expressions lies in the implication that it is indicative of a lack of a proper scientific basis on which to express an opinion.[141]

Subjectivity and Bias

The decision of the court does nonetheless appear to underplay the subjective nature of an expert’s opinion;[144] where seventeen expert DNA examiners were asked to interpret a DNA mixture. The experts not only disagreed but came to varying conclusions as to whether the sample: “cannot be excluded”; should be “excluded”; or whether it was “inconclusive”. This outcome demonstrated that there is potential for subjectivity and bias in DNA analysis; an issue with a seemingly simple solution. If those involved in the testing of DNA were to undertake blind testing of DNA samples then examiners may interpret the results more conservatively, in turn making DNA testing more objective. In practice the idea of blind testing is not a new concept, its use in DNA analysis, however, is highly controversial, with examiners tending to believe that their work requires that they take advantage of all of the information available to them; including the suspects DNA profile.

There is an expectation, especially considering the weight of DNA evidence and its perceived objectivity, ‘that experts reach the same conclusions or, at the very least, similar conclusions’.[146]to allow experts to provide their opinion on the likelihood as to whether the defendant was the individual who left the stain, or to use terminology which may lead the jury to that possible conclusion. The use of verbal equivalents and excessive expert opinion may provide a back door for such an issue.

Chapter 3: Trials and Tribulations

Safeguards and Concerns within an Adversarial Trial

Due to many of the issues, already highlighted in this paper, procedures and safeguards are required within the adversarial trial in order to compensate for the simple fact that your average individual and therefore your average juror is not sufficiently suited for the evaluation of conflicting or complex DNA evidence. It is often claimed that many of the safeguards currently in use are inadequate and as a result, there exists the potential for reform in order to restore confidence in the use of DNA evidence within the criminal trial.

This chapter will, therefore, assess the effectiveness of the existing safeguards and proposed reforms within the adversarial trial, such as cross-examination, whether DNA addresses the right questions, and DNA being the sole evidence.

Cross-Examination

The opportunity afforded by criminal trial to cross-examine an expert is thought to permit the exposure of improprieties and discrepancies in their opinion evidence, and is used to justify the permissive approach to admissibility. It was the judgement of the Supreme Court of the United States in Daubert[149]

As cross-examination relies on the ability of advocates to challenge the evidence of expert witnesses, it requires that they have an understanding of fundamental methodological and statistical concerns. Unfortunately, it is idealistic to presume that advocates possess the necessary knowledge and understanding to adequately address the reliability of technical and complex expert opinion evidence and therefore DNA opinion evidence may suffer from a lack of adequate challenge.[155]

At its worst cross-examination creates a barrier for experts; preventing them from appropriately contextualising or providing an adequate explanation for their answers. As previously stated the adversarial nature permits smooth characters to prosper over their dull counterparts, regardless of the reliability of their evidence; ultimately failing to convey the true probative value of their scientific evidence to the jury, who attach weight, in part, due to the chemistry they possess with those who present it.[156] Thus cross-examination can work to favour the experts who flourish under strict examination.

Irrespective of the validity of the aforementioned concerns, cross-examination remains a successful means of communicating rather complex issues concerning DNA evidence to the jury in a simplified manner and often provides a filter for technical language; reducing the risk that a juror may overvalue or undervalue scientific evidence. It is therefore imperative for expert evidence to be properly debated through cross-examination and if that expert’s opinion is not shared by another expert, countered by evidence to the contrary; facilitated by advocates adequately trained in forensic evidence.

Sole Evidence

Since the case of Adams[161] evidence that the jury may draw inferences from, though it is arguable whether this material qualifies itself as “evidence”. It is more accurate to define the use of DNA evidence as the sole basis of a conviction, as a situation where a DNA profile forms the central and perhaps vital foundation of a prosecution’s case.

For Adams[165] the court nevertheless concluded, rightly or wrongly:

‘that there is nothing inherent in the nature of DNA evidence which makes it inadmissible in itself or which justifies a special, unique rule, that evidence falling into such a category cannot found a conviction in the absence of other evidence’.[166]

The principle of convictions based on DNA evidence alone was considered further in R v FNC.[177]

Following the decision in Lashley[184]

The CSI Effect

The rise in popularity of fictional criminal investigation shows, most notably “Crime Scene Investigation”, has created concern about their effects upon the decision-making skills of jurors. Although the effect is named after the television show of the same name, it can be attributed to the effect mass media has on the perception of the near infallibility of forensic and indeed DNA evidence.[187]

The concern surrounding the “CSI effect” is the suggestion that jurors now have high expectations as to the evidence that should be available to them and are disappointed by the real evidence with which they are presented.[191]

Some jurisdictions have already taken measures in an attempt to combat the perceived effect the television show and the media have had.[193] However, with little empirical evidence to suggest that the “CSI effect” does pose a significant threat to jurors’ decision-making skills, calls for changes to the legal system would appear to be premature. At present appropriate direction from both judges and lawyers concerning the presence, or indeed lack thereof, DNA evidence should be adequate in removing any potential issues caused by the “CSI effect”.

Judicial directions

A judicial direction is seen as necessary so as to bring order to a mass of confusing and complex evidence, judges in many jurisdictions are usually aided in this endeavour through the use of bench books. Since it is unrealistic to expect judges to remember every detail on all areas of the law. Documents such as bench books, aid judges in constructing their directions for the jury, especially when the case concerns complex scientific evidence such as DNA identification; they are however non-binding and many judges will tailor their directions to the case depending on their experience, as should be the case.[194]

In the United Kingdom, the Specimen Directions were intended to alleviate the number of mistakes in judicial directions, providing a formal document to replace the informal notes originally supplied by senior judges. Though they were never intended to provide ‘a magic formula to be used as an incantation’[199]

In R v Bowerman[201] Despite the guidance for the judiciary being very thorough, the issue remains whether judicial directions are fully comprehended by the jury and if they provide an adequate safeguard in their current form.

A study carried out by Professor Cheryl Thomas,[207]

When combined with the complex nature of DNA, written and perhaps other forms of presentation, such as audio-visual aids,[214] judicial directions may afford further and greater protection against miscarriages of justice.

Judge-alone trials

Many people would find the idea of removing juries from criminal trials abhorrent to the idea of justice; it is, however, a practised concept and has been utilised in the United Kingdom in varying cases.[224]

Section 43 of the Criminal Justice Act 2003, before it was repealed, allowed the prosecution to apply for a trial by judge alone in cases of serious or complex fraud; the judge would need to be satisfied that the length or complexity of the case is likely to make the trial so burdensome to members of the jury,[227]

The allure of allowing judges to determine cases with complex expert evidence is the perception that they will be less easily impressed, more aware of its dangers and better equipped to deal with the case.[232] as DNA is often used in serious crimes such as rape or murder, this provision would likely be superfluous.

---

[1] Susan Haack, ‘Trials & tribulations: science in the courts’ (2003) 132 Daedalus 54, 54.

[2] Kimberlianne Podlas, ‘”The CSI Effect”: Exposing the Media Myth’ (2005) 16 Fordham Intellectual Property, Media and Entertainment Law Journal 429.

[3] Lord Thomas of Cwmgiedd (Lord Chief Justice of England and Wales), “Expert Evidence: The Future of Forensic Science in Criminal Trials” (The 2014 Kalisher Criminal Bar Association Lecture, 14 October 2014) 2.

[4] Federal Judicial Centre Reference Manual on Scientific Evidence (3rd ed, National Academy Press, Washington DC, 2011) 52, namely “How Science Works” by David Goodstein.

[5] Joseph L. Peterson (ed), Forensic Science: Scientific Investigation in Criminal Justice (AMS Press 1975) 9.

[6] Goodstein (n 4) 52-53.

[7] Goodstein (n 4), similar comparisons are also drawn in Kelly Pyrek, Forensic Science Under Siege: The Challenges of Forensic Laboratories and the Medico-Legal Investigation System (Elsevier Academic Press 2007) 245-246.

[8] This is true at least of the courts of England and Wales.

[9] Joseph L. Peterson (ed), Forensic Science: Scientific Investigation in Criminal Justice (AMS Press 1975) 5; Susan Haack, ‘A Match Made on Earth: Getting Real About Science and the Law, A’ (2013) 36 Dalhousie Law Journal 39, 52; Susan Haack, Evidence matters: Science, proof and truth in law (Cambridge University Press 2014) 79.

[10] Oriola Sallavaci, The Impact of Scientific Evidence on the Criminal Trial: The Case of DNA Evidence (Routledge 2014) 32.

[11] David Nelken, ‘A Just Measure of Science’ in Paul Roberts (ed), Expert Evidence and Scientific Proof in Criminal Trials (Routledge 2017) 26.

[12] Crown Prosecution service, Expert Evidence (Crown Prosecution Service 2015), An expert witness is simply a witness who provides the court with a statement of opinion on any admissible matter calling for expertise by the witness where they are qualified to give such an opinion, although a professional qualification is not required. Anyone who can convince a judge that their knowledge, skills or training make their testimony of value to the courts can act as an expert witness in a particular case.

[13] Nelken (n 11) 26.

[14] Stephen Breyer ‘Science in the Courtroom’ (2000) 16 Issues in Science and Technology 52 and similarly in Federal Judicial Centre Reference Manual on Scientific Evidence (3rd ed, National Academy Press, Washington DC, 2011) at xiii.

[15] Federal Judicial Centre Reference Manual on Scientific Evidence (3rd ed, National Academy Press, Washington DC 2011) at 52.

[16] Paul Roberts, ‘Paradigms of forensic science and legal process: a critical diagnosis’ (2015) 370(1674) Philosophical Transactions of the Royal Society B: Biological Sciences, 3; Oxford Dictionary of English (3rd edn, Oxford University Press 2010) defines forensic science as “The application of scientific methods and techniques to matters under investigation by a court of law”.

[17] Science and Technology Committee, Forensic Science on Trial (HC 2004–05, 96–I) para 15; National audit office, ‘The Home Office’s oversight of forensic services: Briefing for The House of Commons Science and Technology Committee’ (National Audit Office, December 2014) accessed 28 November 2017 para 16, the National Audit Office highlights the limited data available publicly on forensic spending and the often incomplete, inconsistent, and inaccessible nature of such data; See also Science and Technology Committee, Forensic Science (HC 2013–14, 610) for concerns surrounding the forensic market in England and Wales and more generally Science and Technology Committee, Forensic Science Strategy (HC 2016–17, 501).

[18] R v Robert Lee Clarke (1995) 2 Cr. App. R. 425, 430, Lord Steyn at 430 this was decided per curiam.

[19] Andrei Semikhodskii, Dealing with DNA Evidence: A Legal Guide (Routledge-Cavendish 2007) xi.

[20] R v Clark [2003] EWCA Crim 1020, albeit not a case based on expert evidence concerning DNA analyses, the mistakes involved with the expert evidence are similar to those that can be made when DNA evidence is adduced. The statistics provided by expert witness Doctor Meadow were subject to a number of qualifications which were not addressed, yet formed much of the basis for her conviction. Primarily [94]-[110] and [172]-[180].

[21] Science and Technology Committee, Forensic Science on Trial (HC 2004–05, 96–I) paras 140-142; Law Commission, Expert Evidence in Criminal Proceedings in England and Wales (Law Com No 325, 2011) para 1.5.

[22] Science and Technology Committee, Forensic Science on Trial (HC 2004–05, 96–I) paras 149-150; Criminal Procedure Rules 2010 Part 33, r33.7-33.

[23] Science and Technology Committee, Forensic Science on Trial (HC 2004–05, 96–I) paras 151-152; R v C [2010] EWCA Crim 2578, [39]-[41]; Criminal Procedure Rules 2010 Part 33, r33.6; Law Commission, Expert Evidence in Criminal Proceedings in England and Wales (Law Com No 325, 2011) paras 7.43-7.52.

[24] Law Commission, Expert Evidence in Criminal Proceedings in England and Wales (Law Com No 325, 2011) part 6, summary at 9.15-9.17 and Appendix A Draft Criminal Evidence (Experts) Bill Clause 9. A copy of the flowchart provided in Appendix A is affixed to Appendix A of this paper; Ministry of Justice, The Government’s response to the Law Commission report: “Expert evidence in criminal proceedings in England and Wales” (Ministry of Justice 2013) paras 21-25.

[25] Science and Technology Committee, Forensic Science on Trial (HC 2004–05, 96–I) paras 183-184.

[26] Science and Technology Committee, Forensic Science on Trial (HC 2004–05, 96–I) paras 177-182; Law Commission, The Admissibility of Expert Evidence in Criminal Proceedings in England and Wales: A New Approach to the Determination of Evidentiary Reliability (Law Com CP No 90, 2009), paras 1.15(3) and 6.72-6.74.

[27] Edward Conners and others, Convicted by Juries, Exonerated by Science: Case Studies in the Use of DNA Evidence to Establish Innocence After Trial (National Institute of Justice 1996); Andrei Semikhodskii, Dealing with DNA Evidence: A Legal Guide (Routledge-Cavendish 2007).

[28] Semikhodskii (n 19) 3.

[29] Leander Stewart and others, ‘Differentiating between monozygotic twins through DNA methylation-specific high-resolution melt curve analysis’ (2015) 476 Analytical Biochemistry 36.

[30] National research council, The Evaluation of Forensic DNA Evidence (The National Academies Press 1996) at v.

[31] A. J. Jeffreys, V. Wilson and S. L. Thein, ‘Individual-specific ‘fingerprints’ of human DNA’ (1985) 316 Nature 76.

[32] John M. Butler, Forensic DNA Typing: Biology, Technology, and Genetics of STR Markers (2nd edn, Elsevier Academic Press 2005) 3.

[33] Alec J. Jeffreys, John F. Y. Brookfield and Robert Semeonoff, ‘Positive identification of an immigration test-case using human DNA fingerprints’ (1985) 317 Nature 818.

[34] ibid, ‘The Ghana Immigration case’.

[35] University of Leicester, ‘The Gene Genius’ [2004] Bulletin Supplement August/September.

[36] Robin McKie, ‘Eureka moment that led to the discovery of DNA fingerprinting’ The Guardian (London, 24 May 2009) accessed 11 October 2017.

[37] Suzanne Elvidge, ‘Forensic Cases: Colin Pitchfork, First Exoneration Through DNA’ (Explore Forensics, 2016) accessed 11 October 2017.

[38] Gary Powell, Convicted: Landmark Cases in British Criminal History (Amberley 2018) 241-244.

[39] Todd W. Bille, DNA Analysis: A Powerful Investigative Tool (Profiles in DNA 1999).

[40] Evidence Act 2006 (NZ), for an example.

[41] Criminal Justice Act 1988, s 30.

[42] Criminal Practice Directions Amendment No. 2 [2014] EWCA Crim 1569, New Practice Direction on Expert Evidence, CPD V Evidence 33A, 33A.2; Crown Prosecution service, Expert Evidence (Crown Prosecution Service 2015), 6.

[43] Law Commission, Expert Evidence in Criminal Proceedings in England and Wales (Law Com No 325, 2011), mainly Part 9 and Appendix A Draft Criminal Evidence (Experts) Bill. A copy of the flowchart provided in Appendix A is affixed to Appendix A of this paper.

[44] Ministry of Justice, The Government’s response to the Law Commission report: “Expert evidence in criminal proceedings in England and Wales” (Ministry of Justice 2013), 4; Criminal Procedure Rules 2010 Part 33.

[45] Criminal Practice Directions Amendment No. 2 [2014] EWCA Crim 1569, New Practice Direction on Expert Evidence, CPD V Evidence 33A; CPD V Evidence 19A, 19A.5; Rt Hon Sir Brian Leveson (President of the Queen’s Bench Division), “Review of Efficiency in Criminal Proceedings” (Judiciary of England and Wales, January 2015) 61-62; Michael Stockdale and Adam Jackson, ‘Expert Evidence in Criminal Proceedings: Current Challenges and Opportunities’ (2016) 80 The Journal of Criminal Law 344.

[46] R v Clark (n 20).

[47] Law Commission, The Admissibility of Expert Evidence in Criminal Proceedings in England and Wales: A New Approach to the Determination of Evidentiary Reliability (Law Com CP No 90, 2009), Part 3; Law Commission, Expert Evidence in Criminal Proceedings in England and Wales (Law Com No 325, 2011) para 1.17.

[48] Law Commission, The Admissibility of Expert Evidence in Criminal Proceedings in England and Wales: A New Approach to the Determination of Evidentiary Reliability (Law Com CP No 90, 2009), 3.14; Law Commission, Expert Evidence in Criminal Proceedings in England and Wales (Law Com No 325, 2011) para 1.8; Science and Technology Committee, Forensic Science (HC 2013-14, 610) para 55; Eadaoin O’Brien, Niamh Nic Daeid and Sue Black ‘Science in the court: pitfalls, challenges and solutions’ (2015) 370(20150062) Philosophical Transactions of the Royal Society B: Biological Sciences.

[49] Lord Thomas of Cwmgiedd (Lord Chief Justice of England and Wales), “Expert Evidence: The Future of Forensic Science in Criminal Trials” (The 2014 Kalisher Criminal Bar Association Lecture, 14 October 2014) 5; Rt Hon Sir Brian Leveson (President of the Queen’s Bench Division), “Review of Efficiency in Criminal Proceedings” (Judiciary of England and Wales, January 2015) 61; Lord Thomas of Cwmgiedd (Lord Chief Justice of England and Wales), ‘The legal framework for more robust forensic science evidence’ (2015) 370(1674) Philosophical Transactions of the Royal Society B: Biological Sciences, 2.

[50] Law Commission, Expert Evidence in Criminal Proceedings in England and Wales (Law Com No 325, 2011) para 3.133.

[51] See Appendix A; Science and Technology Committee, Forensic Science (HC 2013-14, 610) paras 53-54; Criminal Practice Directions Amendment No. 2 [2014] EWCA Crim 1569, CPD V Evidence 33A; Crown Prosecution service, Expert Evidence (Crown Prosecution Service 2015), 7.

[52] R v Anthony [2005] EWCA Crim 952.

[53] R v Clark (n 20).

[54] R v Cannings [2004] EWCA Crim 01, as with Clark and Anthony, this case concerned multiple infant deaths in the same family, all three had their convictions quashed by the Court of Appeal.

[55] R v Ward [1993] 1 WLR 619.

[56] ibid, 672-673.

[57] ibid 674-679.

[58] Richard Abbey Graham, The Presentation and Examination of DNA Evidence Adduced During Adversarial Trials (DPhil thesis, University of Leeds 2016) 150 and 178-179.

[59] Science and Technology Committee (n 25) para 141, Professor Black is a Professor of Anatomy and Forensic Anthropology, with considerable experience as an expert witness.

[60] HC Deb 20 April 2006, vol 445, Col 162WH.

[61] Science and Technology Committee, Forensic Science on Trial (HC 2004–05, 96–I) para 140; HC Deb 20 April 2006, vol 445, Cols 144-145WH.

[62] Science and Technology Committee (n 25) paras 140-142, Dr Chris Pamplin is the editor of the UK Register of Expert Witnesses.

[63] William H. Reid, Developing a Forensic Practice: Operations and Ethics for Experts (Routledge 2013) 59-61 and 95-96.

[64] Science and Technology Committee (n 25) para 140.

[65] Bruce Budowle and others, ‘Validity of Low Copy Number Typing and Applications to Forensic Science’ (2009) 50 Croatian Medical Journal 207, 208, recommendations suggest that the maximum template value for an LCN analysis should be less than 200pg.

[66] BBC, ‘DNA test halted after Omagh case’ (BBC News, 23 December 2007) accessed 14 February 2018.

[67] Budowle (n 65) 210.

[68] Budowle (n 65) 213.

[69] Brian Caddy, Graham R Taylor and Adrian M T Linacre, A Review of the Science of Low Template DNA Analysis (Home Office, 11 April 2008) para 1.7; Bruce Budowle and others, ‘Validity of Low Copy Number Typing and Applications to Forensic Science’ (2009) 50 Croatian Medical Journal 207, 210; R v Reed, Reed and Garmson [2009] EWCA Crim 2698, [2010] 1 Cr App R 23 [48]–[49].

[70] R v Sean Hoey [2007] NICC 49; Bruce Budowle and others, ‘Validity of Low Copy Number Typing and Applications to Forensic Science’ (2009) 50 Croatian Medical Journal 207, 208-209.

[71] Brian Caddy, Graham R Taylor and Adrian M T Linacre, A Review of the Science of Low Template DNA Analysis (Home Office, 11 April 2008).

[72] ibid para 7.4.

[73] R v Reed, Reed and Garmson [2009] EWCA Crim 2698, [2010] 1 Cr App R 23 [71]–[76].

[74] ibid [48]–[49].

[75] Caddy (n 71) para 9.3.

[76] Ian W. Evett and Bruce S. Weir, Interpreting DNA Evidence: Statistical Genetics for Forensic Scientists (Sinauer Associates Inc 1998) xiv.

[77] F. Taroni and others, ‘Evaluation and presentation of forensic DNA evidence in European laboratories’ (2002) 42 Science & Justice 21, 22; Richard Abbey Graham, The Presentation and Examination of DNA Evidence Adduced During Adversarial Trials (DPhil thesis, University of Leeds 2016) 284; and more generally, Nadine M. Smit, Ruth M. Morgan and David A. Lagnado, ‘A systematic analysis of misleading evidence in unsafe rulings in England and Wales’ (2018) 58 Science & Justice 128.

[78] Andrei Semikhodskii, Dealing with DNA Evidence: A Legal Guide (Routledge-Cavendish 2007) 51.

[79] Ian W. Evett and Bruce S. Weir, Interpreting DNA Evidence: Statistical Genetics for Forensic Scientists (Sinauer Associates Inc 1998); J. Mortera and A. P. Dawid, ‘Probability and Evidence’ in Tamas Rudas (ed), Handbook of Probability: Theory and Applications (Research Report No.264, Sage Publications 2008) para 2; Roberto Puch-Solis and others, Assessing the Probative Value of DNA Evidence: Guidance for Judges, Lawyers, Forensic Scientists and Expert Witnesses (Royal Statistical Society 2012) paras 4.3-4.7.

[80] Semikhodskii (n 78) 52.

[81] Evett (n 76) 31.

[82] Or sometimes the “Defence attorney’s fallacy”. It is often forgotten that errors in logic may also favour the defendant.

[83] Mike Redmayne and others, ‘Forensic Science Evidence in Question’ [2011] Criminal Law Review 347, 348.

[84] The probability of the match evidence given the prosecution hypothesis. The sign “|” represents the term “given”).

[85] The probability of the match evidence given the defence hypothesis.

[86] Roberto Puch-Solis and others, Assessing the Probative Value of DNA Evidence: Guidance for Judges, Lawyers, Forensic Scientists and Expert Witnesses (Royal Statistical Society 2012) para 4.9.

[87] An example of the prosecutor’s fallacy.

[88] Ian W. Evett and Bruce S. Weir, Interpreting DNA Evidence: Statistical Genetics for Forensic Scientists (Sinauer Associates Inc 1998) 18-22; Andrei Semikhodskii, Dealing with DNA Evidence: A Legal Guide (Routledge-Cavendish 2007) 56-61.

[89] David J. Balding, ‘Interpreting DNA evidence: Can Probability Help Theory’ in Joseph L. Gastwirth (ed), Statistical Science in the Courtroom (Springer 2000) 64-65.

[90] R v Clark [2003] EWCA Crim 1020, [104].

[91] William C. Thompson and Edward L. Schumann, ‘Interpretation of Statistical Evidence in Criminal Trials: The Prosecutor’s Fallacy and the Defence Attorney’s Fallacy’ (1987) 11 Law and Human Behaviour 167; D. J. Balding and Peter Donnelly, “The Prosecutor’s Fallacy and DNA Evidence” [1994] Crim.Law Review 711.

[92] R v Doheny and Adams [1997] 1 Cr. App. R. 369, 372 -374.

[93] David J. Balding, ‘Interpreting DNA evidence: Can Probability Help Theory’ in Joseph L. Gastwirth (ed), Statistical Science in the Courtroom (Springer 2000) 65-66; Roberto Puch-Solis and others, Assessing the Probative Value of DNA Evidence: Guidance for Judges, Lawyers, Forensic Scientists and Expert Witnesses (Royal Statistical Society 2012) paras 7.9-7.11.

[94] R v Clark (n 89) [108].

[95] R v Clark [2003] EWCA Crim 1020, [105], although this is not a case in which DNA evidence was relied upon it stresses the issues that arise when using statistical evidence; R v Clark helped to emphasise the importance of the guidance given in R v Doheny and Adams [1997] Cr. App. R. 369 and contended that the prosecution utilised the statistics to give rise to the prosecutor’s fallacy as identified in relation to DNA statistical evidence in R v Deen (1994) Times Law Review 11 (10 January 1994).

[96] R v Clark (n 89) [96]-[99] and [178].

[97] Letter from Professor Peter Green, President of the Royal Statistical Society to the Lord Chancellor (23 January 2002); R v Clark [2003] EWCA Crim 1020, [178].

[98] As we do not have access to the deliberations of the jury in Ms Clark’s case it cannot be said definitively that their guilty verdict was as a result of this mistake in reasoning, it is however widely accepted that the jury weas influenced by it.

[99] R v Clark (n 89) [103] and [106].

[100] Ray Hill, ‘Multiple sudden infant deaths – coincidence or beyond coincidence?’ (2004) 18 Paediatric and Perinatal Epidemiology 320, specifically 322-323; Norman Fenton, ‘Assessing evidence and testing appropriate hypotheses’ (2014) 54 Science & Justice 502; Professor Meadow failed to consider how likely the two different explanations are: Ms Clark was innocent and suffered an unlikely event, or she was guilty of double infanticide.

[101] R v Clark (n 89) [104], although the judge did attempt to divert the jury away from reliance on statistical evidence.

[102] Jacqueline Horan, Juries in the 21st Century (Federation Press 2012) 125.

[103] D. J. Balding and Peter Donnelly, “The Prosecutor’s Fallacy and DNA Evidence” [1994] Criminal Law Review 711, 716; Bernard Robertson and G. A. Vignaux, Interpreting Evidence: Evaluating Forensic Science in the Courtroom (Wiley 1995) 19-21.

[104] Jonathan J. Koehler, ‘Error and Exaggeration in the Presentation of DNA Evidence at Trial’ (1993) 34 Jurimetrics Journal 21, 27-31.

[105] The random match probability.

[106] Or put another way, when the probability of DNA evidence (Random match probability) is equated with the probability of the accused being the source of the suspect DNA.

[107] R v Doheny and Adams (n 92) 372-374.

[108] R v Doheny and Adams (n 92) 369-370

[109] R v Adams (Stafford Crown Court, 27 March 1991).

[110] R v Doheny and Adams (n 92) 383.

[111] R v Doheny and Adams (n 92) 377-378.

[112] David J. Balding and Christopher D. Steele, Weight-of-Evidence for Forensic DNA Profiles (2nd edn, John Wiley & Sons 2015) 168.

[113] R v Doheny and Adams (n 92).

[114] Koehler (n 104) 31.

[115] Koehler (n 104) 31-32.

[116] R v Doheny and Adams (n 92) 372-374.

[117] R v Doheny and Adams [1997] 1 Cr. App. R. 369, 373; Peter Donnelly, ‘Appealing statistics’ (2005) 2 Significance 46, 47.

[118] People v Orenthal James Simpson, case number BA097211, an American case which popularised DNA evidence.

[119] Bernard Robertson and G. A. Vignaux, Interpreting Evidence: Evaluating Forensic Science in the Courtroom (Wiley 1995) 93-94; David J. Balding, ‘Interpreting DNA evidence: Can Probability Help Theory’ in Joseph L. Gastwirth (ed), Statistical Science in the Courtroom (Springer 2000) 65-66; Andrei Semikhodskii, Dealing with DNA Evidence: A Legal Guide (Routledge-Cavendish 2007) 116-117; This is similar to the example of 1 in 26 potential matches in the United Kingdom being construed as the probability of defendant being innocent being 26 to 1.

[120] R v Deen (1994) Times Law Review 11 (10 January 1994); R v Doheny and Adams [1997] 1 Cr. App. R. 369, 373; David J. Balding, ‘Interpreting DNA evidence: Can Probability Help Theory’ in Joseph L. Gastwirth (ed), Statistical Science in the Courtroom (Springer 2000) 65.

[121] Jonathan J. Koehler, ‘One in Millions, Billions, and Trillions: Lessons from People v. Collins (1968) for People v. Simpson (1995)’ (1997) 47 Journal of Legal Education 214, 219; Andrei Semikhodskii, Dealing with DNA Evidence: A Legal Guide (Routledge-Cavendish 2007) 114-115.

[122] R v Doheny and Adams (n 92) 373.

[123] R v Adams (No.1) [1996] 2 Cr. App. R. 467; R v Adams [1996] Crim. L.R. 898; R v Adams (No.2) [1998] 1 Cr. App. R. 377.

[124] R v Adams (No.1) [1996] 2 Cr. App. R. 467, 469; R v Adams [1996] Crim. L.R. 898; R v Adams (No.2) [1998] 1 Cr. App. R. 377, 381.

[125] Peter Donnelly, ‘Appealing statistics’ (2005) 2 Significance 46, 46-47 ‘This case was unusual in having DNA evidence pointing one way and all the other evidence pointing the other way; Adams also had a half-brother who was in his twenties but his DNA was never tested.

[126] Association of Forensic Science Providers, ‘Standards for the formulation of evaluative forensic science expert opinion’ (2009) 49 Science and Justice 161, 163.

[127] R v Bilal [2005] EWCA Crim 1555, handwriting analysis; R v Atkins [2010] 1 Cr. App. R. 8, facial-mapping; R v Bull [2010] EWCA Crim 2542, facial-mapping.

[128] R v T [2010] EWCA Crim 2439.

[129] ibid.

[130] Redmayne (n 83) 351.

[131] R v T (n 129) [90].

[132] R v Dlugosz and Others [2013] EWCA Crim 2, [2013] 1 Cr. App. R. 32.

[133] ibid.

[134] ibid [11].

[135] A verbal equivalent.

[136] Graham (n 58) 127.

[137] Criminal Practice Directions Amendment No. 2 [2014] EWCA Crim 1569, New Practice Direction on Expert concerning CPD V Evidence 33A, 33A.5; CPD V Evidence 19A, 19A.5.

[138] Law Commission, Expert Evidence in Criminal Proceedings in England and Wales (Law Com No 325, 2011), 9.12.

[139] Law Commission, Expert Evidence in Criminal Proceedings in England and Wales (Law Com No 325, 2011), 9.11; Criminal Practice Directions Amendment No. 2 [2014] EWCA Crim 1569, New Practice Direction on Expert concerning CPD V Evidence 33A, 33A.6; CPD V Evidence 19A, 19 A.6.

[140] R v Dlugosz and Others (n 133) [14].

[141] R v Dlugosz and Others (n 133) [2]-[28].

[142] R v Dlugosz and Others (n 133) [26].

[143] Semikhodskii (n 78) 58-60.

[144] Itiel E. Dror and Greg Hampikian, ‘Subjectivity and bias in forensic DNA mixture interpretation’ (2011) 51 Science and Justice 204.

[145] Itiel E. Dror, ‘A Hierarchy of Expert Performance’ (2016) 5 Journal of Applied Research in Memory and Cognition 121, 121.

[146] R v Doheny and Adams (n 92) 369-370 and 374-375.

[147] Daubert v Merrell Dow Pharmaceuticals 509 US 579 (1993).

[148] ibid 596.

[149] Law Commission, Expert Evidence in Criminal Proceedings in England and Wales (Law Com No 325, 2011), para 1.20.

[150] ibid para 1.21.

[151] An American jurist and expert in the law of evidence.

[152] John Henry Wigmore, Evidence in Trials at Common Law (volume 5, Little Brown and Company 1974) 32.

[153] Paul Roberts, ‘Renegotiating forensic cultures: Between law, science and criminal justice’ (2013) 44 Studies in History and Philosophy of Biological and Biomedical Sciences 47, 56.

[154] Law Commission (n 149) para 1.21.

[155] Penny Darbyshire, Andy Maughan and Angus Stewart, Research Papers in Law: What Can the English Legal System Learn from Jury Research Published up to 2001? (Kingston2002) 23; James M. Shellow, ‘The Limits of Cross-Examination’ (2003) 34 Seton Hall Law Review 317.

[156] Paul Roberts ‘Renegotiating forensic cultures: Between law, science and criminal justice’ (2013) 44 Studies in History and Philosophy of Biological and Biomedical Sciences 47, 56.

[157] R v Adams (Stafford Crown Court, 27 March 1991)

[158] R v Adams (No.1) [1996] 2 Cr App R 467; R v Adams (No. 2) [1998] Cr App R 377.

[159] Mike Redmayne, Expert Evidence and Criminal Justice (Oxford University Press 2001) 58.

[160] Criminal Justice Act 2003, Part 11, Chapter 1; Criminal Justice Act 2003, s 103(1); R v Bryon [2015] EWCA Crim 997, the prosecution case consisted solely of DNA found on duct tape at the scene and previous conviction of a similar offence,

[161] Criminal Justice and Public Order Act 1994, s 34-39; R v Cowan [1996] QB 373; R v Dervish [2001] EWCA Crim 2789.

[162] R v Adams (No.1) [1996] 2 Cr. App. R. 467; R v Adams [1996] Crim. L.R. 898; R v Adams (No.2) [1998] 1 Cr. App. R. 377.

[163] Peter Donnelly, ‘Appealing statistics’ (2005) 2 Significance 46, 46.

[164] Michael Lynch and others, Truth Machine: The Contentious History of DNA Fingerprinting (The University of Chicago Press 2008) 190-199.

[165] R v Adams (No.1) [1996] 2 Cr. App. R. 467, 467.

[166] ibid 467 and 469.

[167] R v FNC [2016] 1 W.L.R. 980.

[168] R v Lashley [2000] EWCA Crim 88; R v Grant [2008] EWCA Crim 1890; R v Ogden [2013] EWCA Crim 1294.

[169] Criminal Justice Act 2003, s 58, a general right of appeal in respect of rulings.

[170] R v FNC (n 167) [6].

[171] R v FNC (n 167) [13]-[18].

[172] R v Adams (No.2) [1998] 1 Cr. App. R. 377.

[173] R v Sampson Kelly [2014] EWCA Crim 1968, DNA evidence alone may provide evidence of possession of a prohibited firearm.

[174] R v FNC (n 167) [28].

[175] R v FNC (n 167) [27].

[176] R v Lashley [2000] EWCA Crim 88; R v Grant [2008] EWCA Crim 1890; R v Ogden [2013] EWCA Crim 1294; R v FNC [2016] 1 W.L.R. 980, [27]-[30] a per curiam decision.

[177] R v Tsekiri (Jonathan) [2017] EWCA Crim 40; R v FNC [2016] 1 W.L.R. 980, ‘It must be open to question, in the light of the recent marked improvements in the techniques of analysis of DNA, whether the authorities from which that distinction derives were correctly decided and whether the fact that the DNA was on an article left at the scene of the crime ought to be sufficient to raise a case to answer where the match is in the order of one in a billion’.

[178] R v Lashley [2000] EWCA Crim 88.

[179] Crown Prosecution service, Guidance on DNA Charging (Crown Prosecution Service 2004), para 5.1; See also Appendix B and C of this paper.

[180] ibid para 5.4.

[181] R v Grant [2008] EWCA Crim 1890, the defendant did not dispute that the DNA sample was his, or that it had been found at the crime scene, but stated that it was deposited at the scene innocently.

[182] R v Doheny and Adams [1997] 1 Cr. App. R. 369, 373 ‘The possibility that two of the only 26 men in the United Kingdom with the matching DNA should have been in the vicinity of the crime will seem almost incredible and a comparatively slight nexus between the defendant and the crime, independent of the DNA, is likely to suffice to present an overall picture to the jury that satisfies them of the defendant’s guilt.

[183] Crown Prosecution service, Expert Evidence (Crown Prosecution Service 2015), 44-50; Andrew Rennison, Report into the circumstances of a complaint received from the Greater Manchester Police on 7 March 2012 regarding DNA evidence provided by LGC Forensics (Forensic Science Regulator 17 September 2012); Andrew Rennison, The Performance of Cellmark Forensic Services R v. [S] (Forensic Science Regulator 6 December 2013); Andrew Rennison, The Performance of Bedfordshire Police and Key Forensic Services Re Bedfordshire Submission [A] (Forensic Science Regulator 16 December 2013).

[184] Tony Ward, ‘DNA Evidence Alone as a Case to Answer: R v FNC [2015] EWCA Crim 1732’ (2016) 80 The Journal of Criminal Law 7.

[185] Kimberlianne Podlas, ‘”The CSI Effect”: Exposing the Media Myth’ (2005) 16 Fordham Intellectual Property, Media and Entertainment Law Journal 429; Jeffrey Heinrick, ‘Everyone’s an Expert: The CSI Effect’s Negative Impact on Juries’ (Arizona State University 2006) Accessed 24 March 2018; Tom R. Tyler, ‘Viewing CSI and the threshold of guilt: Managing truth and justice in reality and fiction’ (2006) 115 The Yale Law Journal 1050; N.J. Schweitzer and Michael J. Saks, ‘The CSI Effect: Popular Fiction About Forensic Science Affects the Public’s Expectations About Real Forensic Science’ (2007) 47 Jurimetrics 357; Tamara F. Lawson, ‘Before the Verdict and Beyond the Verdict: The CSI Infection Within Modern Criminal Jury Trials’ (2009) 41 Loyola University Chicago Law Journal 119; Jason M. Chin and Larysa Workewych, ‘The CSI Effect’ (Oxford Handbooks Online 2016) Accessed 24 March 2018.

[186] Steven M. Smith, Veronica Stinson and Marc W. Patry, ‘Fact or Fiction? The Myth and Reality of the CSI Effect’ (2011) 47 Court Review: The Journal of the American Judges Association 4, 6.

[187] Kimberlianne Podlas, ‘”The CSI Effect”: Exposing the Media Myth’ (2005) 16 Fordham Intellectual Property, Media and Entertainment Law Journal 429; Tom R. Tyler, ‘Viewing CSI and the threshold of guilt: Managing truth and justice in reality and fiction’ (2006) 115 The Yale Law Journal 1050; Jason M. Chin and Larysa Workewych, ‘The CSI Effect’ (Oxford Handbooks Online 2016) Accessed 24 March 2018.

[188] N.J. Schweitzer and Michael J. Saks, ‘The CSI Effect: Popular Fiction About Forensic Science Affects the Public’s Expectations About Real Forensic Science’ (2007) 47 Jurimetrics 357, 358.

[189] “The Strong Prosecutor’s Effect” Simon A. Cole and Rachel Dioso-Villa, ‘CSI and its Effects: Media, Juries, and the Burden of Proof’ (2007) 41 New England Law Review 435, 447-448; Steven M. Smith, Veronica Stinson and Marc W. Patry, ‘Fact or Fiction? The Myth and Reality of the CSI Effect’ (2011) 47 Court Review: The Journal of the American Judges Association 4, 4; Jason M. Chin and Larysa Workewych, ‘The CSI Effect’ (Oxford Handbooks Online 2016) Accessed 24 March 2018, 3.

[190] “The Defendant’s Effect” Simon A. Cole and Rachel Dioso-Villa, ‘CSI and its Effects: Media, Juries, and the Burden of Proof’ (2007) 41 New England Law Review 435, 449-450; Steven M. Smith, Veronica Stinson and Marc W. Patry, ‘Fact or Fiction? The Myth and Reality of the CSI Effect’ (2011) 47 Court Review: The Journal of the American Judges Association 4, 4; Jason M. Chin and Larysa Workewych, ‘The CSI Effect’ (Oxford Handbooks Online 2016) Accessed 24 March 2018, 3-4.

[191] “The Weak Prosecutor’s Effect” Simon A. Cole and Rachel Dioso-Villa, ‘CSI and its Effects: Media, Juries, and the Burden of Proof’ (2007) 41 New England Law Review 435, 448-449; Steven M. Smith, Veronica Stinson and Marc W. Patry, ‘Fact or Fiction? The Myth and Reality of the CSI Effect’ (2011) 47 Court Review: The Journal of the American Judges Association 4, 4; Jason M. Chin and Larysa Workewych, ‘The CSI Effect’ (Oxford Handbooks Online 2016) Accessed 24 March 2018, 3.

[192] Jason M. Chin and Larysa Workewych, ‘The CSI Effect’ (Oxford Handbooks Online 2016) Accessed 24 March 2018, 16-21.

[193] Simon A. Cole and Rachel Dioso-Villa, ‘Should Judges Worry about the ‘”CSI Effect”?’ (2011) 47 Court Review: The Journal of the American Judges Association 20, 30; see also Simon A. Cole and Rachel Dioso-Villa, ‘CSI and its Effects: Media, Juries, and the Burden of Proof’ (2007) 41 New England Law Review 435, 444; Jason M. Chin and Larysa Workewych, ‘The CSI Effect’ (Oxford Handbooks Online 2016) Accessed 24 March 2018, 19.

[194] Although this is not always true.

[195] Sir David Maddison and others, The Crown Court Compendium: Part I: Jury and Trial Management and Summing Up (Judicial college November 2017), para 1.3.

[196] ibid.

[197] Judicial Studies Board, Crown Court Bench Book: Directing the Jury (Judicial Studies Board March 2010), 137-147.

[198] Simon Tonking and John Wait, Crown Court Bench Book Companion (Judicial College October 2011), 67.

[199] Sir David Maddison (n 194) para 15.8.

[200] R v Bowerman [2000] 2 Cr. App. R. 189.

[201] ibid 189.

[202] Cheryl Thomas, Are Juries Fair? (Ministry of Justice Research Series 1/10, 2010)

[203] ibid vi.

[204] ibid vi and 37-38.

[205] ibid vi and 38, 17% increase in comprehension.

[206] Sally Elizabeth Nelson, Directing Jurors in England and Wales: The Effect of Narrativisation on Comprehension (DPhil thesis, University of Cardiff 2013), 22: for further concerns.

[207] Penny Darbyshire, Andy Maughan and Angus Stewart, Research Papers in Law: What Can the English Legal System Learn from Jury Research Published up to 2001? (Kingston2002), 52; Sally Elizabeth Nelson, Directing Jurors in England and Wales: The Effect of Narrativisation on Comprehension (DPhil thesis, University of Cardiff 2013), 51-53.

[208] Neil Brewer, ‘Sophie Harvey and Carolyn Semmler, Improving Comprehension of Jury Instructions with Audio-Visual Presentation’ (2004) 18 Applied Cognitive Psychology 765; Sally Elizabeth Nelson, Directing Jurors in England and Wales: The Effect of Narrativisation on Comprehension (DPhil thesis, University of Cardiff 2013), 51-59.

[209] R v C [2011] EWCA Crim 1607.

[210] Although this was insufficient to overturn the conviction.

[211] R v Deen (1994) Times Law Review 11 (10 January 1994), the expert witness and the judge were guilty of fallacious reasoning; R v Clark [2003] EWCA Crim 1020.

[212] R v Doheny and Adams [1997] 1 Cr. App. R. 369, 375 the court supplied a textual template for judicial direction where random match probability is concerned, to be ‘tailored to the facts of the particular case’; Roberto Puch-Solis and others, Assessing the Probative Value of DNA Evidence: Guidance for Judges, Lawyers, Forensic Scientists and Expert Witnesses (Royal Statistical Society 2012) 118-119; Richard Abbey Graham, The Presentation and Examination of DNA Evidence Adduced During Adversarial Trials (DPhil thesis, University of Leeds 2016), para 7.4.

[213] Mike Redmayne, Expert Evidence and Criminal Justice (Oxford University Press 2001) 58, although it has been suggested that despite this better understanding it may not stop jurors falling into the trap; Science and Technology Committee, Forensic Science on Trial (HC 2004–05, 96–I) paras 177-182; Law Commission, The Admissibility of Expert Evidence in Criminal Proceedings in England and Wales: A New Approach to the Determination of Evidentiary Reliability (Law Com CP No 90, 2009), paras 1.15(3) and 6.72-6.74; Roberto Puch-Solis and others, Assessing the Probative Value of DNA Evidence: Guidance for Judges, Lawyers, Forensic Scientists and Expert Witnesses (Royal Statistical Society 2012), 2-4 and 99-100.

[214] Criminal Procedure Rules 2010 Part 25, r25.14.

[215] This case was heard in the Crown court, although the Magistrates hear cases without a jury they have very limited sentencing and try more minor cases, less than 1% of cases in the criminal courts will be determined by a jury. It is also worth noting that the Civil courts almost exclusively try cases without a jury; Rebecca Huxley-Binns and Jacqueline Martin, Unlocking The English Legal System (Routledge 2013) 144-150; Ministry of Justice, Criminal court statistics quarterly, England and Wales: April to June 2016 Ministry of Justice Statistics Bulletin (Ministry of Justice 2016), 2.

[216]John Jackson and Sean Doran, Judge Without Jury: Diplock Trials in the Adversary System (Clarendon Press 1995).

[217] Justice and Security (Northern Ireland) Act 2007, non-jury trials in Northern Ireland are often still referred to as Diplock Courts.

[218] HC Deb 20 December 1972, vol 848, col 1341-7; Lord Diplock, Report of the Commission to consider legal procedures to deal with terrorist activities in Northern Ireland (Cmnd 5185, 1972).

[219] Gary Powell, Convicted: Landmark Cases in British Criminal History (Amberley 2018) 266-268; A right laid down by the Magna Carta.

[220] R v Twomey and others [2010] 1 W.L.R. 630; R v Twomey and others (No 2) [2011] 1, W.L.R. 1681, jury tampering was considered a very significant danger; Clive Coleman, ‘The debate behind holding a criminal trial without jury’ (BBC News, 12 January 2010) Accessed 25 March 2018; Gary Powell, Convicted: Landmark Cases in British Criminal History (Amberley 2018) 266-268.

[221] Criminal Justice Act 2003, Part 7.

[222] Criminal Justice Act 2003, s 43; Protection of Freedoms Act 2012, s 133 repealed section 43 (non-jury trials for cases of serious and complex fraud) of the Criminal Justice Act 2003.

[223] Criminal Justice Act 2003, s 44.

[224] Criminal Justice Act 2003, s 46.

[225] Having regard to steps that may be reasonably taken to reduce the complexity or length of the trial, as long as those steps couldn’t be regarded as significantly disadvantaging the prosecution.

[226] Rebecca Huxley-Binns and Jacqueline Martin, Unlocking the English Legal System (Routledge 2013) 145.

[227] Indeed some jurisdictions have legislated to that effect; Criminal Procedure Act 2011 (NZ), s 102, as do parts of Canada, Australia and America.

[228] Penny Darbyshire, Andy Maughan and Angus Stewart, Research Papers in Law: What Can the English Legal System Learn from Jury Research Published up to 2001? (Kingston2002), 41.

[229] Oriola Sallavaci, The Impact of Scientific Evidence on the Criminal Trial: The Case of DNA Evidence (Routledge 2014) 171-173.

[230] Robert D. Myers, Ronald S. Reinstein and Gordon M. Griller, ‘Complex Scientific Evidence and the Jury’ (1999) 83 Judicature 150.

[231] Andrea Roth, ‘Defying DNA: Rethinking the Role of the Jury in an Age of Scientific Proof of Innocence’ (2013) 93 Boston University Law Review 1643.

[232] Similar to Criminal Procedure Act 2011 (NZ), s 102(1)(a).