Thousands of convicted criminals could be freed from Scottish jails following a European ruling that interviewing suspects without their lawyer present is a breach of human rights.

The test case, heard by the European Court of Human Rights, upheld the claim by Yusuf Salduz, 25, a Turkish national, that he was unfairly denied a lawyer when questioned by police eight years ago.

Leading lawyers claim the ruling is likely to have “dire consequences” for Scotland’s criminal justice system, under which suspects do not have an automatic right to have a lawyer present during police questioning.

They believe the ruling paves the way for prisoners to appeal against their convictions where incriminating evidence or confessions were obtained without a lawyer being present.

Niall McCluskey, a human rights advocate, said there was a “strong argument” that the absence of a solicitor while in police custody constitutes a breach of the European Convention.

“When this decision is fully implemented into Scots law, there is the likelihood of people who have committed and admitted the most abominable crimes being released from prison,” said Paul McBride, one of Scotland’s leading QCs and an adviser to the Scottish Conservatives.

“It is a horrific thought that criminals convicted under Scotland’s robust legal system could be freed on this technicality,” said Annabel Goldie, the leader of the Scottish Conservatives.

Senior police have already held meetings with the Crown Office to discuss the potential ramifications of the Turkish case.

A test case from Forfar has been referred to the Court of Criminal Appeal in Edinburgh and a case in Falkirk has been adjourned.

Salduz was arrested in 2001 on suspicion of taking part in an illegal demonstration in support of the imprisoned leader of the the Kurdistan Workers’ party.

Salduz, who was under 18 at the time of the offence, was denied legal assistance while in custody, during which time he made a confession to police that he later claimed was under duress.

Earlier this year, the European Court of Human Rights ruled that Article 6 of the European Convention had been violated. It requires that “access to a lawyer should be provided as from the first interrogation of a suspect by the police,” unless there are “compelling reasons” to restrict this right.

In 2001, the Scottish courts decided that Article 6 did not create a universal right for an accused to have access to a solicitor before or during questioning by the police.

Legal experts claim that decision is under threat following the court’s ruling in the Salduz case.

A spokesman for Kenny MacAskill, the justice secretary, accused opposition parties of “scaremongering”.

“Criminal justice procedures here in Scotland are radically different from those in Turkey,” he said.

“Scots law has served us well for years. We need to balance the rights of our communities and police with the rights of the accused.

“The matter is now before the Appeal Court in Edinburgh. This speculation from the Tories is irresponsible.”

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