POLICE Scotland have launched an investigation into the possible unlawful disclosure of material related to Alex Salmond’s criminal trial and Nicola Sturgeon’s husband.

The force confirmed it had been instructed by Scotland’s prosecution service to look into the leak of WhatsApp messages purporting to come from SNP chief executive Peter Murrell. 

It follows former SNP Justice Secretary Kenny MacAskill claiming he was sent messages in which Mr Murrell appeared to back police action against the former first minister.

Mr MacAskill, who is the MP for East Lothian, said this week he was sent the messages anonymously and had passed them to prosecutors and a Holyrood inquiry.

The messages purport to show Mr Murrell backing prosecution action against Mr Salmond in January 2019, the month he won a civil legal battle against Ms Sturgeon’s government and was seperately charged with mutiple counts of sexual assault.

Mr MacAskill said he wanted the Scottish Parliament and Crown Office to “investigate the contents of this document”.

READ MORE: SNP MP calls for probe into Sturgeon's husband over Salmond affair

One possible line of inquiry is that the messages are part of a cache of WhatsApp data involving SNP officials which was obtained by Mr Salmond’s legal team as part of his trial defence, and which was referred to during a preliminary court hearing.

It can be a criminal offence for a person to knowingly use or disclose information disclosed for the purpose of criminal proceedings for another purpose.

Mr Salmond launched a judicial review against the Government after it held a sexual misconduct probe into him in 2018 following complaints about his time as First Minister.

He had the exercised set aside by showing the probe was “tainted by apparent bias” because the investigating official had been in prior contact with his accusers.

His Court of Session victory left taxpayers with a £512,000 bill for his costs, and a Holyrood inquiry is now investigating how the Government bungled the probe and legal case.

Shortly after Mr Salmond won his civil action, he was charged with sexual assault, which led to a criminal trial earlier this year at which he was acquitted on all 13 counts.

His supporters have since claimed he was the victim of a conspiracy by senior figures in the SNP who wanted to stop him making a political comeback and rivalling Ms Sturgeon.

READ MORE: Sturgeon's government accused of 'cloak and dagger' leak to damage Salmond

The Press & Journal today reported that the leak of the WhatsApp data was now the subject of a police inquiry - something the Crown Office has also verified.  

A Police Scotland spokesperson said: "The Crown Office and Procurator Fiscal Service has instructed us to investigate the potential unlawful disclosure of material. 

“Enquiries are at an early stage."

The WhatsApp leak is the latest murky twist in the bitter feud between Mr Salmond and Ms Sturgeon, with the Holyrood inquiry now appearing to add fuel to the flames.

Mr Murrell, who married Ms Sturgeon in 2010, is expected to be questioned under oath by MSPs on the inquiry about his knowledge of the botched probe into Mr Salmond and what action the SNP took at the time.

He claimed in written evidence his wife did not tell him about the probe despite Mr Salmond raising it with her in the couple’s house in April 2018, while he was at also at home.

Despite its scepticism about that, the inquiry is not expected to publish the WhatsApp messages about Mr Murrell because of concerns over their provenance.

Tory MSP Murdo Fraser, who sits on the Holyrood inquiry, said: “Scottish people will be disgusted by the staggering information coming from SNP ranks about what happened here.

“I would expect Scottish Government ministers, particularly the justice secretary, to make it clear that no-one asked them to intervene in this case on any side or at any time.

"If political pressure was applied to the police in any sense, the public must hear it.

“In the middle of all this murkiness, the only thing that’s clear is the SNP are keeping the truth covered up.

"They won’t release the key documents and they’re making the Salmond inquiry a sham.”