POLICE Scotland has been called on to have no investigatory role into claims by a leading detective that the force acted criminally by spying on him.

MSPs believe the allegations made by DI David Moran against the force’s Counter Corruption Unit (CCU) should be examined by an external organisation.

Graeme Pearson, Labour's justice spokesman, said: "It is very difficult for Police Scotland to investigate itself in this case and the only way to satisfy ourselves is to bring in an outside body".

Police forces must get judicial approval before using the Regulation of Investigatory Powers Act (RIPA) to unmask a journalist’s source.

However, following an investigation by the Sunday Herald, the IOCCO watchdog confirmed last year that Police Scotland had committed five “reckless” breaches of the spying rules.

The force unlawfully tried to find out whether four serving and retired police officers passed information to a newspaper about the original investigation into the murder of sex worker Emma Caldwell.

Moran, a ‘Murder Squad’ detective who has over thirty years policing experience, revealed this week that he was one of the four officers targeted.

In a letter to the Justice Committee, Moran furiously denied any suggestion of leaking information and wrote that deputy chief constable Neil Richardson had given “outrageous” evidence about him to MSPs on the spying scandal.

He also wrote that the CCU actions had been wilful, not just reckless:

“Consequently I have made a complaint to the Police and the Procurator Fiscal through my solicitor that I believe I am a victim of a crime and that the course of conduct followed was wilful and therefore a criminal action.”

The complaint, lodged on Moran’s behalf by his lawyer Peter Watson, means a serving detective has made criminal allegations about his own force.

The Crown Office takes the lead on such complaints and can get police officers to investigate, but Pearson said:

“In a single police service, it’s difficult to see where independent scrutiny can be achieved when internal criminal inquiries are required. I predicted this difficulty would come up at some point. We have no fallback.”

Alternatives include tasking either a police force from another part of the UK, or instructing Scotland’s Police Investigations and Review Commissioner (PIRC).

However, Highlands and Islands MSP John Finnie flagged up a potential problem with the PIRC in this instance:

“One option of course is to have PIRC deal with the administration of such complaints directly, by-passing the deputy chief constable. However, I understand that in this case a number of those working for PIRC may have had, either directly or indirectly, involvement in the Emma Caldwell investigation which started this whole chain of events off.”

PIRC Director of Investigations John Mitchell worked on the original Caldwell probe when he was at Strathclyde Police, but there is no suggestion he could not carry out a fair investigation into the Moran claims.

A Crown Office spokesperson confirmed correspondence from DI Moran's lawyer had been received.

A PIRC spokesman said: “The Crown Office and Procurator Fiscal Service (COPFS) has the responsibility to investigate allegations of criminal conduct against police officers and they would determine the appropriate authority to undertake such an investigation on their behalf.”

A Police Scotland spokesperson said: "The matter has been referred to the Scottish Police Authority as is normal where complaints against senior officers are received."