The trial of Ross Monaghan for the murder of Kevin "The Gerbil" Carroll in an Asda car park in Glasgow, which ended in an acquittal, raised serious concerns about forensic evidence in criminal cases but the fact that an independent report into those concerns has not been made public is disturbing.
The trial was conducted in public, the judge's criticisms of the evidence were made in public and the criticisms have been investigated by a public body. The investigation should be made public too.
The initial concerns about the trial centred on two main areas. The first was the collection of DNA evidence and the risk of contamination. Police officers who searched Mr Monaghan's home found a single particle of firearms discharge residue but they were wearing uniforms they had worn earlier on a firearms training exercise, meaning their clothing could have been covered with bullet residue.
The second area of concern was over the relationship between police and forensic staff at the Scottish Police Services Authority (SPSA), which now falls under the Scottish Police Authority (SPA). Forensic experts should be independent and maintain a professional distance from the police to prevent a miscarriage of justice, but a forensic expert told the trial that she filed a report stating the residue particle was of a similar type to that used in cartridges recovered from the crime scene because a police officer asked her to do so.
At the time, the trial judge Lord Brailsford strongly criticised these elements of the investigation, saying he found the evidence of the forensic expert disturbing and making it clear the search of Mr Monaghan's home gave rise to contamination. They were criticisms that had to be thoroughly investigated to ensure such serious oversights were not repeated and an investigation was duly carried out by the Home Office Forensic Science Regulator, which monitors standards for the provision of forensic services to the criminal justice system.
However, the SPA has revealed it does not intend to make the result of the investigation public on the advice of the Crown Office, which says making the report public could jeopardise a future prosecution.
It is right for the Crown Office to be mindful of future proceedings but its conclusion is questionable and has been criticised by both Brian McConnachie, the chairman of the Faculty of Advocates Criminal Bar Association, and the solicitor advocate John Scott. Mr McConnachie says he cannot see how a report into the original evidence would impact on any future case while Mr Scott has suggested that, if the Crown has genuine concerns about the effect on any future case, the report could be edited to protect against such a risk, which is a sensible suggestion.
The other problem with the Crown's response is it suggests that, as long as no-one is convicted of the murder, the report should remain out of the public domain and that cannot be acceptable. The outcome of an investigation arising from a trial conducted in public should be published for the sake not only of those with a direct interest in the case but also because the public as a whole has a legitimate interest in the investigation and its consequences for the criminal justice system. The public deserve to know what mistakes were made and how they will be avoided in future.