Introduction
29.1. A conclusion which accepts the opinion of one expert witness in preference to that of another does not necessarily imply any criticism of the expert whose opinion is not preferred.
Mr Leadbetter
29.2. The Inquiry has no criticism to make of Mr Leadbetter. It is evident from paragraph 236 of chapter 25 that something went wrong in his ridge counts when plotting his charting of Y7. Mr Leadbetter was honestly and genuinely seeking to assist the Inquiry and the fact that his charting may have gone wrong is not a matter calling for any further comment.
Mr Graham
29.3. Some of the SCRO examiners who agreed that the mark was made by Ms McKie did so only at the level of an elimination (i.e. on less than 16 points), while others made an identification to the full 16-point legal standard. SCRO as a bureau failed properly to assess the implications of that division of opinion, particularly at the stage when the Crown was investigating a perjury charge against Ms McKie. Mr Graham's conclusion on Y7 was based on finding less than 16 points in sequence and agreement (possibly as low as seven points) and was therefore at the level of an elimination. Mr Graham recognised that that finding would not have supported a prosecution of Ms McKie, assuming that the Crown were to apply the legal standard of 16 points, and he was so acutely alert to this distinction that he was prepared to put on record with Mr Gilchrist (who it must be recalled was investigating a criminal complaint against SCRO examiners), and to reaffirm at the Inquiry hearing, that he believed the SCRO examiners had gone wrong in trying to find 16 points in agreement.1 In these circumstances I have no criticism of Mr Graham.
Mr Berry
29.4. Mr Berry gave evidence to the Justice 1 Committee on 26 June 2006 supportive of the identification of Y7.2 He has given statements to the Inquiry confirming his opinion that Y7 was correctly identified. One dated 29 January 2009 was made available to the Inquiry on 29 July 2011. Mr Berry also provided a witness statement dated 10 August 2011.3 Reliance on the Daily Mail reproduction of Ms McKie's print was central to his opinion. Leaving aside the conflict between Mr Swann and Mr Berry as to whether that was a plain or a rolled impression,4 the fact is that both relied on a newspaper copy of the fingerprint. That is dealt with below in the context of Mr Swann's evidence. No criticism is made of Mr Berry.
Mr Mackenzie and Mr Swann
29.5. I do not criticise Mr Mackenzie or Mr Swann but there are some issues raised by their evidence that are of more general relevance and that is now considered.
Mr Mackenzie
29.6. Mr Mackenzie's initial conclusion was only that Y7 could be eliminated as the left thumb print of Ms McKie.
Neither of those findings would have supported an identification to the then 16-point standard.
29.7. By the time of the presentation at Tulliallan in August 2000 Mr Mackenzie was reporting a total of 45 matching second and third level details, with 16 "traditional ridge characteristics"7 in the lower segment, consistent with an identification.
29.8. This was a joint presentation with Mr Dunbar but the illustrated comparisons in the booklet 'McKie Case Revisited'8 was based essentially on work carried out by Mr Mackenzie9 and will, therefore, be attributed to him.
29.9. The initial findings of Mr Mackenzie were based on the lower part of Y7 only. Those initial conclusions were erroneous probably due to a combination of the factors already discussed in chapter 28. Those factors will have still been in play to some extent in the Tulliallan presentation but additional factors must account for the substantial increase in the number of matching points being reported.
29.10. Of the additional factors that may have influenced Mr Mackenzie, three can be highlighted.
29.11. The first is that the presentation was influenced by the insight afforded by courses on 'ridgeology' after February 199710 which enabled Mr Mackenzie to include third level detail (such as pores and incipient ridges) in his Tulliallan presentation and that accounts for six of the 22 points identified in the lower segment of the mark.11 Care requires to be taken when relying on third level detail and given the lack of clarity in the mark such detail was in my view unreliable in this case.12
29.12. The second influence is that Mr Mackenzie had access, after the trial, to an internet copy of a left thumb print of Ms McKie taken by Mr Wertheim.13 Mr Mackenzie said that access to that copy enabled him to identify additional ridge detail in the mark because that print showed more detail above the fault line and to the top right than was shown in the police prints.14 Fifteen of the points (points 31-45) shown in the presentation (a combination of second and third level detail)15 derived from an examination of the internet copy print. Mr Mackenzie was critical of others who based their opinions on an examination of internet copies16 but contradicted himself by basing part of his own presentation on just such a copy. The copy that he used contains evidence of 'damage' or 'disturbance' in the area to which Mr Mackenzie drew attention on pdf page 19 of the booklet17 and in paragraphs 212 and 213 of chapter 25 it has already been observed that the internet copy appears to contain 'details' which are absent from originals of known provenance. Evidence based on copies can be inadmissible in civil and criminal courts in Scotland and the rationale for the rule is that experience has shown that copying processes can cause distortion that renders the copy unreliable. Even in the digital age that risk remains and was manifest in this instance: the copy used did contain signs of distortion. The presence of 'damage' or 'disturbance' in the copy image used by Mr Mackenzie undermined the integrity of the image and hence its reliability. Evidence based on cherry-picking some detail from a copy image of doubtful integrity would be inadmissible as a matter of Scots law as contravening the 'best evidence rule'18 and an examiner ought not to rely on a copy image containing signs of damage or otherwise being of uncertain integrity.
29.13. Not all of the detail in the upper part of the mark depends on the internet copy print and that leads to the third matter that requires to be highlighted. Points 23-30 in the Tulliallan charting on pdf pages 12 and 13 of the presentation booklet are identified relative to a left thumb print in the police elimination form dated 18 February 1997, which was available to Mr Mackenzie on that date. Of those, points 23-28 are 'traditional' ridge characteristics.19 This part of the Tulliallan presentation probably reflects the benefit of the additional detailed study that Mr Mackenzie carried out after the trial in the knowledge that the SCRO examiners had been questioned about the upper segment.20 The fact remains that the material that he studied (the plain impression in the police elimination form dated 18 February 1997) was available to the examiners at SCRO at that date and it did show significant level two characteristics in the upper section of the mark. This confirms the conclusion that the SCRO examiners, Mr Mackenzie included, had insufficient reason to discount that part of the mark in 1997 and were in error in reaching a conclusion based on an incomplete comparison of the mark as a whole.
Mr Swann
29.14. The complication of reliance on 'copies' also arises at two points in the evidence of Mr Swann. The first concerns the materials that he studied in February/March 1999 and the second concerns the Daily Mail image.
29.15. As noted in paragraphs 20 and 25 of chapter 11 Mr Swann had repeatedly asked for access to original materials and Levy & McRae made that request to the Crown on a number of occasions without success. In the event, Mr Swann was presented with a photocopy of a charted enlargement in Production 15221 and formed a concluded view by reference to that copy material prior to viewing original materials on 2 March 1999. Mr Swann returned the copy to Levy & McRae22 and it has not been recovered. I have been unable to see it for myself and therefore I cannot comment on the quality of the reproduction but Mr Swann's evidence was that it was "adequate for the job I had to do but it was not obviously as clear as the original. It could not have been."23
29.16. There is no personal criticism of Mr Swann, nor Levy & McRae for that matter, for using the limited material that was made available to them. Evidence derived from study of copy materials in such circumstances would fall within the exception to the 'best evidence' rule and hence would have been admissible in court24 but that misses the point. Mr Swann was being instructed to advise Ms McKie on the SCRO fingerprint evidence and no examiner instructed by the defence, no matter how experienced, should be put in the predicament of having to study photocopied materials.
29.17. There were two added complications in relation to the copy initially studied by Mr Swann. The first is that, being a copy of the charted enlargement in Production 152, it showed only the lower part of the mark. He will, therefore, have formed his conclusion on identity without the opportunity to assess the import of the differences in the upper part. Secondly, the very fact that it contained charted markings made by SCRO would be contrary to the normal procedures for independent analysis of the mark and posed the risk of 'guided interpretation' or reverse reasoning. Examiners instructed by the defence, as much as any other examiner, require to carry out an analysis of the mark uninfluenced by knowledge of the detail in the print. They need to be given not only first generation images (as opposed to photocopies) but also images clear of any marking by another examiner. Part of the exercise of advising an accused person may include commenting on any prosecution charting, but any charting should be studied only after the examiner has had the opportunity to study clean images of the mark and print.
29.18. It was not until some date after the Daily Mail printed a copy of Ms McKie's fingerprint in October 2000 that Mr Swann was able to satisfy himself that there was an explanation for the upper part of the mark. Comment has already been made in chapter 25 from paragraph 228 on the unreliability of using copies such as that in the Daily Mail; and even then the problem remained that Mr Swann could not point to a pattern of movement that could account for the mark as a whole.
Commentary
29.19. Having found image quality to be a critical variable I conclude that the fact that Mr Mackenzie and Mr Swann at various stages relied on copies (digital and paper) may well have been a contributory factor in the errors that they made relative to Y7.
29.20. As with the four SCRO examiners who signed the joint reports, another contributory factor will have been concentration on the lower part of the mark. In the case of Mr Swann that was all that was available to him when he first formed his conclusion but having formed the view at that stage that there were at least 16 points in sequence and agreement in the bottom part sufficient to prove identity to a level of 100% certainty it is easy to understand that at later stages, even when he studied the Kent image of the whole mark, differences in the top section may not have weighed sufficiently with him.
29.21. No imputation of any impropriety is intended by this conclusion. Mr Mackenzie falls into the same general category as his colleagues in SCRO discussed in chapter 28. The error on his part has to be seen in the context that external experts of standing and experience made the same mistake. As for Mr Swann, I bear in mind that he demonstrated his independence by testifying to a misidentification in the McNamee case.25 I am entirely satisfied that Mr Mackenzie and Mr Swann genuinely believe the marks Y7 and QI2 Ross to have been correctly identified. That examiners of their standing and experience can have made a mistake in this instance reinforces the conclusion that even examiners of the utmost experience can fall into error when they are working at the margins of tolerance with complex marks such as Y7 and QI2 Ross.
1. See chapter 28 paragraph 80
2. Scottish Parliament Justice 1 Committee Official Report 26 June 2006 Col 3494
3. TS_0055; this includes (at pdf page 52ff) his statement dated 29 January 2009
4. See chapter 25 para 200
5. FI_0046 para 124 Inquiry Witness Statement of Mr Mackenzie and Mr Mackenzie 30 September page 45
6. FI_0046 para 152 Inquiry Witness Statement of Mr Mackenzie and Mr Mackenzie 30 September pages 49, 96ff
7. CO_0050 pdf page 6
8. CO_0059 and SG_0282
9. FI_0053 para 192 Inquiry Witness Statement of Mr Dunbar (see also para 188)
10. Mr Mackenzie 30 September page 25ff
11. CO_0059 pdf page 14 (and SG_0282)
12. See chapter 25 para 152
13. Mr Mackenzie 30 September page 53ff
14. FI_0046 para 188 Inquiry Witness Statement of Mr Mackenzie
15. CO_0059 pdf page 15 (and SG_0282)
16. FI_0046 paras 181, 215 Inquiry Witness Statement of Mr Mackenzie
17. CO_0050 pdf page 6 and CO_0059 pdf page 19 (and SG_0282)
18. Chapter 30; and see chapter 25 para 266
19. CO_0050 pdf page 6 and CO_0059 pdf pages 12-13 (and SG_0282)
20. FI_0046 para 248 Inquiry Witness Statement of Mr Mackenzie and CO_0050 pdf page 6
21. ST_0006h
22. Mr Swann 21 October pages 10-11
23. Mr Swann 27 November pages 4-5; see also chapter 11 para 25
24. See chapter 30 para 13
25. FI_0149 pdf pages 33-34 (para 5.3) Inquiry Witness Statement of Mr Swann