Summary of decision is this case following a reference from the Scottish Criminal Cases Review Commission

In a hearing to decide deciding whether the “expert” evidence referred to as case linkage analysis was admissible as evidence, the court found that in its present state of development it was not considered to be admissible in these proceedings.

Thomas Ross Young was convicted at the High Court in Glasgow on 25 October 1977 of eight charges on an indictment. All but one of the offences involved violence towards women and many involved a significant sexual element.  The most serious charge was in relation to the murder of Frances Baker.

On 2 November 1977 the appellant lodged a note of appeal against conviction, but on 3 January 1978 this appeal was abandoned. 

On 12 September 2005 Strathclyde Police wrote to the appellant’s solicitors explaining that Strathclyde Police and Lothian and Borders Police were currently undertaking “Operation Trinity”, a joint investigation into the murders of six women in 1977, including the murder of Frances Barker, and stating that the police, at the request of the procurator fiscal, wished to interview the appellant about the murder of Frances Barker. 

As a result of this interview, the appellant formed the view that the police no longer believed that he murdered Frances Barker.  If the safety of the murder conviction was open to question, this called into question the safety of the other convictions, because the appellant was convicted on the basis of the Moorov doctrine (similar fact evidence).  Accordingly, the appellant made an application to the Scottish Criminal Cases Review Commission for review of his conviction. 

In the course of the Commission’s consideration of the appellant’s application, the Crown Office forwarded to the Commission a copy of the report Strathclyde Police had sent to Crown Office in respect of the Operation Trinity investigation, in which it is stated that the police had re-investigated the murders of six young women, including Frances Barker, between 11 June and 2 December 1977.

Appended to the Operation Trinity report were three further reports, namely a report by John Clark and Marjorie Black, forensic pathologists of the University of Glasgow; a report by the Behavioural Analysis Unit at the Federal Bureau of Investigation, Quantico, Virginia, USA and a report in which data relating to all homicides of female victims in Scotland between 1968 and 2004.

Reference was made in the report to what were described as “unique similarities” between the murders, and the report expressed the conclusion that the same person(s) were responsible for all murders within a short time frame.  The hypothesis which underlay the conclusion of the Operation Trinity investigation was that it may be possible to link crimes to form a series on the basis of perpetrator behavioural similarity, to enable a conclusion to be reached as to the likelihood of the crimes being perpetrated by the same person or persons.  Although in the course of these proceedings this practice was referred to by several names, the court referred to it throughout as “Case Linkage Analysis” (“CLA”). 

The Commission considered the various reports which were placed before it, and the appellant’s statement to the Commission.  It addressed the test for additional evidence, and concluded that the terms of the Operation Trinity report were likely to have had a material bearing on, or a material part to play in, the jury’s determination of the critical question which was put to them by the trial judge, namely “the question which you have to decide is whether you are satisfied beyond reasonable doubt that the accused is the person who murdered Frances Barker.  The Commission concluded that there may have been a miscarriage of justice and that it was in the interests of justice that the case should be referred to this court.  Accordingly the Commission made a reference to this court in November 2007.

The appellant lodged grounds of appeal on 6 June 2008.  Despite the best efforts of the court to make progress, there then followed a very protracted procedural history, involving several changes of senior counsel and prolonged investigation.  Further procedural difficulties then occurred, and the hearing on the admissibility of CLA evidence did not take place until the summer of 2013.

CLA has not only been an important element in the Operation Trinity report and the Commission’s conclusion, but has formed a very substantial part of the grounds of appeal since 2008.  Throughout the appeal procedure the Crown has adopted the position that CLA is not evidence that could competently have been admitted at the original proceedings nor is it now admissible in the appeal. 

There are several aspects of the methodology of CLA which at present suggest that it is not yet reliable.  Most studies do not take account of victimology, and the effect of a victim’s reaction and behaviour on the behaviour of the offender.  Research to date is concerned only with closed, or solved, crimes, and it is not apparent that it can safely be applied to predictions, or unsolved crimes.  Inter-rater reliability remains a real issue, and there appears to be no agreed or uniform procedure (either within the UK or worldwide) to check and certify this.  Indeed, there are no agreed international or national standards in the field of CLA.  Even in the best conditions, with the best researchers using the best practices, there is still a high number of false positives and false negatives and no satisfactory explanation has yet been found for this.

It may be for these reasons that CLA evidence does not appear to have been given in any court anywhere thus far.  Considering all of the evidence it may be that CLA has developed to the stage that it may be of assistance to those charged with the investigation of crimes, as an aid in the search for other real evidence, although the court expressed no view on this. 

The court therefore reached the clear conclusion that CLA evidence in its present state of development and as explained by Professor Canter and Dr Woodhams, is not admissible in these proceedings.

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