POLICE Scotland refused to allow an outside force tasked with investigating an illegal spying operation to interview officers at the centre of the scandal, it has been claimed.

Retired detective David Moran said it was “high farce” that Police Scotland denied Durham Constabulary access to officers in the tarnished Counter Corruption Unit (CCU).

In 2015, officers in the CCU used the Regulation of Investigatory Powers Scotland (RIPA) to find out if serving and retired officers had a role in the leaking of information in the Emma Caldwell murder case.

However, the snoop was unlawful and Police Scotland asked Durham Constabulary to consider the non-criminal complaints into the case.

Durham completed its probe earlier this year and handed over reports to the single force, which is led by Chief Constable Phil Gormley, and the Scottish Police Authority.

The English force is believed to have recommended apologies for the victims and backed misconduct proceedings for officers who were in the CCU at the time.

Moran, one of the individuals who was unjustly targeted by the force, said Durham was not allowed to speak to the CCU officers.

“When Durham finished their inquiry, they said they wanted to interview these people. They had deliberately not spoken to them because they had identified them as subjects of an inquiry rather than witnesses,” he said. “Police Scotland refused to let them do that.”

It is understood the decision related to the interpretation of the Police Scotland misconduct rules.

Durham believed they were conducting an investigation, but midway through the process it was decided the exercise was an inquiry.

Moran said: “The person conducting the misconduct inquiry must be independent of everything that has went before.

“They’re [Police Scotland] saying that Durham weren’t independent of everything that went before because they had carried out an investigation. To me, it is just high farce.”

The single force has since tasked the Police Service of Northern Ireland with dealing with the misconduct side and several officers are going through the disciplinary process.

A Durham Constabulary spokeswoman said: “Following the conclusion of Durham Constabulary’s inquiry, we are aware that an independent investigation is now being carried out by the Police Service of Northern Ireland (PSNI). It would therefore be inappropriate for us to comment.”

Chief Superintendent Alan Speirs, head of professional standards at Police Scotland, said it would “not be appropriate” to comment until after the PSNI completed its independent misconduct investigation on behalf of the force.