34.1. In Part 4 of this Report I give a detailed analysis of the evidence to the Inquiry regarding a small number of fingerprints associated with and leading up to a particular criminal trial in Scotland in 1999, HMA v McKie. Since I had the benefit of an active, informed debate during which I heard about the methodologies used by fingerprint practitioners and the competing explanations they provided concerning the marks and prints at issue, I was put in a position in which I could arrive at my own conclusions.
34.2. I have found that SCRO were in error in identifying Y7 as having been made by Ms McKie and in identifying QI2 as having been made by Miss Ross. There was a misidentification of Y7 and QI2 Ross.
34.3. The evidence did not provide a basis for findings that the errors arose because of a specific failure or mishap. Rather, as set out in Part 5, the evidence indicates that recognised risk factors were present and I consider that these provide a reasonable explanation for the errors.
34.4. The question then arises as to how the risk of such errors happening might be minimised. As with any field of human endeavour I do not consider that the risk of error can be excluded totally but my terms of reference require me to make recommendations as to what measures might now be introduced to ensure that any 'shortcomings' are avoided in the future.
34.5. The case in question was more than a decade ago, and accordingly I took evidence as to current practice in order to inform my consideration of what new measures might be introduced. I heard evidence as to practice in Scotland and other parts of the United Kingdom and also, to a limited extent, elsewhere. I also had the benefit of a review of relevant literature prepared for the Inquiry,1 and access to various reports such as those of the National Academy of Sciences in the United States of America and the OIG reports of 20062 and 20113 following the Brandon Mayfield case.
34.6. My conclusions are based on the evidence before me. I have found it instructive, however, that as will be seen at various places in the chapters in this Part, my conclusions, in many respects, accord with conclusions in the OIG and National Academy of Sciences reports which demonstrate that the factors that I have identified as having contributed to the errors in relation to Y7 and QI2 Ross are not isolated, local considerations but cast light on the fundamental premises of fingerprint comparison as a forensic discipline and the 'limits of performance'4 of the discipline.
34.7. In considering recommendations I have had to reflect with particular care on the facts that (1) there is no reason to suggest that fingerprint comparison is an inherently unreliable form of identification and (2) fingerprint evidence continues to be rarely challenged and is most often treated as routine. Recommendation of new measures has to approach the subject with a sense of perspective.
Current practice in perspective
Fingerprint evidence in the criminal justice system
34.8. Evidence given by Mrs Tierney gives some perspective to a review of current practice. She provided statistics relating to the workload of the Edinburgh bureau between April 2008 and March 2009. The bureau processed just short of 1500 cases, of which ninety resulted in requests for statements for court purposes. The bulk of the work was, accordingly, providing intelligence to the police to assist with investigations.5 Of the ninety cases where a request for a report was made, thirteen related to High Court proceedings, fourteen were for sheriff and jury cases and the rest were for summary proceedings.6 On only three occasions was there a request for oral evidence and this was not to respond to a challenge from a defence expert but was by way of explanation.7
34.9. Mr Pattison gave corresponding statistics for the prevalence of fingerprint evidence in High Court cases generally. Between April and September 2009 there were 228 trials indicted to the High Court. Twelve of those trials featured fingerprint evidence. In nine of those cases the fingerprint evidence was agreed between prosecution and defence in a joint minute of agreement, thereby dispensing with the need for an examiner to give evidence in person. In only three cases did an examiner give oral evidence at a trial. In none of those three cases was there a challenge to identification. Rather evidence was led from an examiner for incidental reasons.8 In one case the prosecutor wanted to draw an inference from the position of the print. In the other cases the defence would not agree the fingerprint evidence: in one case because the defence had an interest in another unidentified mark found at the scene; and in the other because the defence challenged the process by which the prints had been taken.9
34.10. There are no comprehensive statistics for trials before a sheriff and jury but in the same period Mr Pattison was aware of only three cases in which oral evidence was led from a fingerprint examiner.10
34.11. The relative infrequency of examiners being required to give evidence in person at trials can be viewed from a different perspective. As at the date of the Inquiry, Mr McGinnies, who qualified in 2004,11 had not given evidence in court in any case,12 while Mrs Tierney had never given evidence in a case in which a defence expert was expressing a different view.13
34.12. This is reflected in other jurisdictions. In London the position is similar, with most identifications and eliminations not proceeding to court. Mr Pugh said that it should be recognised that fingerprints play an important part in the investigation of crime, particularly the early stages of crime investigation.14 28,000 cases of volume crime, such as burglary and vehicle crime, came in to the Metropolitan Police bureau in 2008-2009 to have finger marks searched against the database or compared against a nominated suspect. This generated around 6000 suspect identifications and 3700 legitimate access identifications. The balance was either unusable or unidentified.15 Of those volume crime cases the Metropolitan Police was asked to prepare evidence in around 770 cases.16 Not all of the 770 cases were contested.17 Mr Pugh offered a number of reasons why most of the 6,000 identifications did not result in a requirement to give evidence, including the finding of other compelling evidence (e.g. the police may find the stolen property in the possession of the suspect on arrest), or the individual may plead guilty.
34.13. Mr Chamberlain said that in his experience in England the identification of fingerprints is rarely challenged in courts18 and that accorded with the experience of Mr Logan in Northern Ireland who had not given evidence in a case involving a disputed mark.19 Mr Chamberlain suggested that the lack of challenge was due to a general public perception, shared by the judiciary, that fingerprint evidence is irrefutable and safe and a lack of defence expertise. Challenges tended to be collateral and not substantive. Normal lines of defence were legitimate access to the site of the mark, attacking the chain of evidence and, occasionally, discrediting the examiner.20
34.14. That is not confined to the United Kingdom. The National Academy of Sciences notes that: "Over the years, the courts have admitted fingerprint evidence, even though this evidence has 'made its way into the courtroom without empirical validation of the underlying theory and/or its particular application'. The courts sometimes appear to assume that fingerprint evidence is irrefutable."21
Standards in the provision of fingerprint evidence
34.15. The Inquiry heard evidence from Mr Andrew Rennison, the Forensic Science Regulator for England and Wales. The scope of regulation spans the whole investigative and judicial process and encompasses standards for organisations providing forensic science services, the competence of practitioners and the validation of methods.22 He drew a distinction between regulation of (1) organisations providing forensic science services, (2) practitioners and (3) the techniques being applied.23
34.16. Many of the earlier investigations and reviews concerning SCRO dealt with issues such as the overall structure of fingerprint services in Scotland. There has been considerable structural change in relation to the delivery of fingerprint services in Scotland. In 2007, the Glasgow bureau, with the other SFS bureaux, became part of the Scottish Police Services Authority (SPSA) established under the Police, Public Order and Criminal Justice (Scotland) Act 2006. This legislation has made arrangements for the independence of SPSA, structurally, from police forces or any individual police force. The SPSA is subject to financial and performance audits by the Auditor General for Scotland and I have not considered it part of my remit to review its general structural or operational arrangements.24
34.17. In chapter 40 I do consider the regulation of organisations and practitioners but, in reviewing the evidence to the Inquiry, my focus has come to be upon the techniques that are applied by fingerprint examiners. The Inquiry has confirmed previous studies that there is variability among fingerprint practitioners in relation to observation of ridge detail in fingerprints, the interpretation of observed detail and the consequent conclusion as to whether or not a match can be made.
Assessing fingerprint evidence
34.18. My findings relative to QI2 Asbury demonstrate that a finding of identity can be made despite a difference among fingerprint examiners in relation to incidental details. But differences between examiners may go deeper than incidental detail. Y7 serves as a contrast to QI2 Asbury. There were variations in detail among the examiners in SCRO and the external experts Mr Graham and Mr Swann who were agreed as to the identification and I concluded that, properly understood, those differences were indicative of an unreliable identification of Y7. In coming to that conclusion I was in the fortunate position that the Inquiry had not only detailed evidence from those who supported the identification, but also the benefit of the insight of contradictors who alleged that Y7 had been misidentified, and the same was true of QI2 Ross.
34.19. The existence of a contradictor may be a matter of chance in another case. The challenge for individual fingerprint examiners is to be alert to the potential for error and to guard against it when formulating their opinions; and, for the legal system, the challenge is that the reliability of fingerprint evidence may have to be assessed without the benefit of a contradictor.
34.20. All forensic evidence should be approached with an open and questioning mind both by those who practise the discipline and by the legal community. It should not be assumed that any forensic evidence is irrefutable or infallible, if only because of the risk of human error. Nor should it be assumed that any form of forensic evidence is necessarily routine. Fingerprint evidence is no different. There is no evidence before the Inquiry to suggest that fingerprint evidence as a class is inherently reliable. On the other hand there is no basis for a claim to infallibility. It is opinion evidence and where appropriate, it should be subject to robust scrutiny and challenge. Mr Tom Nelson, SPSA's Director of Forensic Services, welcomed forensic evidence being challenged because he recognised that the expert was in court to provide the best evidence so that the court could reach a decision.25
34.21. The legal profession, judges and juries need to be alert to the subjective nature of fingerprint evidence and to the other factors of relevance to the assessment of the opinion of a fingerprint examiner in order to consider this evidence on its merits. However, as the National Academy of Sciences has observed: "Judicial review [i.e. scrutiny], by itself, will not cure the infirmities of the forensic science community" in part due to the limitations of the adversarial process.26 That observation is made all the more telling by the statistics quoted above as regards the small proportion of cases that actually reach court. There is a need for the forensic science community to improve.
Improving fingerprint evidence
34.22. I have already observed that it is necessary to have a sense of perspective. As Judge Edwards said: "we cannot throw out the baby with the bath water as we work to improve the science underlying forensic practice."27 That comes through in the report of the committee of the National Academy of Sciences that he co-chaired:
"Historically, friction ridge analysis has served as a valuable tool, both to identify the guilty and to exclude the innocent. Because of the amount of detail available in friction ridges, it seems plausible that a careful comparison of two impressions can accurately discern whether or not they had a common source. Although there is limited information about the accuracy and reliability of friction ridge analyses, claims that these analyses have zero error rates are not scientifically plausible."28
34.23. Fingerprint comparison continues to serve as a valuable source of evidence but practice can be improved. The operative words are "a careful comparison". The reliability of fingerprint evidence depends in part on the robustness of the methodology of fingerprint comparison and the structures within which examiners practise, including proper training and accreditation of examiners and effective management of the ACE-V protocol to which they work. At the same time, it has to be recognised that it is not realistic to expect a zero error rate and therefore the reliability of fingerprint evidence depends on a proper appreciation by fingerprint examiners, and the legal community, of the limitations of the discipline and in particular the subjective nature of the judgments that underlie a fingerprint opinion and the many variable factors of relevance to it.
The structure of this Part
34.24. The chapters in this Part consider (1) the methodology of fingerprint identification, (2) ACE-V, (3) the documentation of fingerprint work and court reports, (4) the expression of opinion by examiners and implications for the presentation of evidence, (5) the need for special treatment of 'complex' marks, (6) accreditation and training of examiners, performance management and expert witness status and (7) research and the role of statistics.
34.25. Current practice is reviewed and recommendations are made to seek to ensure that fingerprint work is undertaken as carefully and as reliably as possible and also that the basis for conclusions reached by fingerprint examiners is properly disclosed so that those who have to assess the evidence are given the means to do so.
1. EC_0001:The Current Position of Fingerprint Evidence - a Literature Review C. J. Lawless, I. C. Shaw and J. Mennell, School of Applied Sciences, Northumbria University
2. US Department of Justice, Office of the Inspector General (2006) Review of the FBI's Handling of the Brandon Mayfield Case (Unclassified and Redacted) (US Department of Justice) URL:
3. US Department of Justice, Office of the Inspector General (2011) A Review of the FBI's Progress in Responding to the Recommendations in the Office of the Inspector General Report on the Fingerprint Misidentification in the Brandon Mayfield Case URL:
4. See Judge Edwards, "Solving the Problems That Plague the Forensic Science Community", keynote address at the conference on Forensic Science for the 21st Century: The National Academy of Sciences Report and Beyond, Arizona State University, 3 April 2009, page 3. URL:
5. Mrs Tierney 12 November pages 95-97
6. Mrs Tierney 12 November page 175
7. Mrs Tierney 12 November pages 174-175
8. Mr Pattison 13 November pages 182-183
9. FI_0195 para 5 Inquiry Witness Statement (Supp.) of Mr Pattison
10. FI_0195 para 7 Inquiry Witness Statement (Supp.) of Mr Pattison
11. FI_0193 para 2 Inquiry Witness Statement of Mr McGinnies
12. Mr McGinnies 4 November page 124
13. Mrs Tierney 12 November page 199
14. Mr Pugh 24 November pages 84-85
15. Mr Pugh, Mrs Redgewell 24 November pages 105-111 and MP_0008
16. Mr Pugh 24 November page 109
17. Mr Pugh, Mrs Redgewell 24 November pages 109-110
18. Mr Chamberlain 18 November page 60
19. Mr Logan 16 November page 35
20. Mr Chamberlain 18 November page 61, Champod C. and Chamberlain P. Fingerprints, in: Fraser J. and Williams R. (eds) Handbook of Forensic Science, Willan Publishing, 2009, page 80
21. Committee on Identifying the Needs of the Forensic Sciences Community, Committee on Science, Technology and Law Policy and Global Affairs, Committee on Applied and Theoretical Statistics Division on Engineering and Physical Sciences, National Research Council. Strengthening Forensic Science in the United States: A Path Forward, Washington, D.C.: National Academies Press, 2009, page 102
22. EB_0001 para 5
23. Mr Rennison 8 July pages 80-81
24. Audit Scotland (2010) The Scottish Police Services Authority, (Audit Scotland), URL:
25. Mr Nelson 13 November page 7
26. NAS, Strengthening Forensic Science in the United States: A Path Forward, 2009, page 110
27. Judge Edwards, "Solving the Problems That Plague the Forensic Science Community", 2009 page 9
28. NAS, Strengthening Forensic Science in the United States: A Path Forward, 2009, page 142