MINISTERS are facing growing pressure for a public inquiry into the Shirley McKie affair after a Sunday Times investigation discovered that fingerprint evidence involved in the acquittal of a convicted murderer was flawed.

Danish fingerprint experts, whose report in 2000 led to the acquittal of David Asbury, who had been jailed two years earlier for the murder of bank clerk Marion Ross, have admitted that some of their findings were wrong.

They have written to the Crown Office claiming that their conclusions — which also led to the suspension of four fingerprint experts at the Scottish Criminal Records office (SCRO) and prompted a police investigation — were partly based on the wrong documents.

The flawed findings were only one strand of the evidence used to acquit Asbury, but provide further ammunition for those who have questioned the handling of the whole McKie affair. The executive has been accused of settling with McKie rather than face an embarrassing court case, where fingerprint evidence would have come under close scrutiny.

The error came to light when Michael Pass, an independent expert, was commissioned by the Crown Office last month to examine the Danish report.

The case gained notoriety after McKie, a former detective-constable with Strathclyde police, was wrongly accused of perjury after it was alleged her fingerprints were found on a door frame at the murder scene in February 1997. She was awarded £750,000 in compensation by the Crown Office in an out-of-court settlement earlier this month, after a nine-year campaign to clear her name.

Last night opposition politicians said the latest findings provide compelling evidence to justify a full public inquiry. They plan to raise the issue in the Scottish parliament this week.

“I don’t think the position of the justice department and the Crown Office is sustainable, they are burying their heads in the sand,” said Nicola Sturgeon, the SNP’s deputy leader.

“We will push this matter in parliament this week and do everything we can to bring this into the open. There are a number of reports which the crown is refusing to publish including those connected to the Asbury case. All of that can’t just be brushed under the carpet.”

Annabel Goldie, the Scottish Conservative leader, said: “This is a fascinating development. The whole chronicle of events is shrouded with allegation and counter-allegation and uncertainty. The public interest now demands that the executive orders a judicial inquiry.”

Asbury, a joiner from Kilbirnie in Ayrshire, was jailed for life in January 1997 for the murder of Ross, a 51-year-old single woman who was stabbed in her Kilmarnock home.

Asbury denied murdering the woman and stealing a biscuit tin containing £1,400, maintaining that money in a tin found at his home was his life savings.

At his trial SCRO experts gave crucial evidence that a fingerprint found on the tin was made by Ross.

However, he was freed in August 2002 by appeal court judges after his lawyers successfully argued that he had suffered a miscarriage of justice.

They said the evidence of SCRO experts had been “substantially discredited”, citing evidence from the Danish report, which concluded that the print found on the tin did not belong to Ross, and that a fingerprint on one of the £10 notes thought to be from Ross’s flat was not made by Asbury.

They now accept that they reached the wrong decision, claiming they were supplied with the wrong documents.

Asbury is seeking £150,000 in damages for his wrongful imprisonment. Cameron Fyfe, the lawyer who is representing Asbury, said: “The appeal court took the view that the most important piece of evidence against my client was Ross’s alleged print on the tin and we are sticking by our assertion that that was not hers.”

It has emerged that in July 2000, a year before Asbury was freed, Robert McKenzie, the deputy head of the SCRO’s fingerprint bureau, was asked to examine the biscuit tin by William Gilchrist, a senior fiscal in Paisley. In his report McKenzie listed 29 matching characteristics with Ross’s right forefinger and said he was in “no doubt” of a match.

Another fingerprint expert, Peter Swann, a former Home Office adviser, claims to have identified more than 20 matching characteristics and will meet SCRO officials this week to make his findings public.

Last week it emerged that the Crown Office was told five years ago that after the original mistake had been made over McKie’s print it was covered up in a “criminal” manner.

On Friday Colin Boyd, the lord advocate — who is facing a motion of no confidence, justified his decision not to bring charges against anyone over the alleged cover-up.

In a letter to George Reid, the presiding officer, he said that he chose not to proceed with a criminal case because of “conflicting evidence” from fingerprint experts.

Iain McKie, Shirley’s father, said he believed that there had been a catalogue of errors by the SCRO followed by a crude attempt to cover their tracks. “The whole thing is a shambles. We are facing incompetence of an unparalleled nature,” he said.

A Scottish executive spokesperson said: “(The Pass) report was commissioned recently as part of the executive’s preparations for the civil court case brought against Scottish ministers by (Shirley) McKie. As there is a separate civil case against Scottish ministers involving David Asbury, it would be inappropriate to comment about any of the content of that report.”

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