POLICE Scotland is under mounting pressure to say whether the timing of the arrest of former SNP chief executive Peter Murrell was influenced by the party’s recent leadership race.

Murrell, the husband of the former SNP leader Nicola Sturgeon, was arrested on Wednesday morning as police officers searched both the couple’s house and party HQ in Edinburgh. He was released without charge later that day, but that has done little to quell the political fall-out.

The dramatic scenes came less than two weeks after the conclusion of the SNP leadership race, which was narrowly won by Humza Yousaf, and figures in the party have told The National the contest may have ended differently if the arrest had happened sooner.

READ MORE: No evidence police were digging up Peter Murrell’s garden

Senior SNP MP Angus MacNeil, who as chair of Westminster’s International Trade Committee also sits on the top-level Liaison Committee, said there were key questions for Police Scotland to answer which had an impact on the functioning of democracy.

“In an ever-changing situation we have to know: did the leadership contest influence the police’s timing? I think that’s a question for Police Scotland and I think for democracy it’s very important that the police answer that question.

“Did a political process affect the timing of the police investigation? If it did, then it’s got implications for democracy, because the members may or may not have selected the same candidate, but we don’t know.”

A second SNP parliamentarian told this paper they were “certain” the outcome of the close-run leadership race would have been different if Murrell’s arrest had happened weeks earlier.

The National: Nicola Sturgeon with her husband Peter MurrellNicola Sturgeon with her husband Peter Murrell (Image: PA)

MacNeil went on: “If a lot of people are asking the question ‘did they delay the investigation’ then Police Scotland have to clear that up.

“The problem we have, and the problem that we’ve had for a while, is people making decisions without information. People voting before they knew [about the membership numbers controversy], HQ then telling Mi-Voice that under no circumstances are people allowed to change their votes given the new information.

“We had a process, a voting period, where information changed but people weren’t allowed to change their votes if they wanted to.

“Everything’s changing but the vote can’t change, and if the police have held back the investigation then that means information was withheld from those who voted. Did they delay it and if so why did they delay it?”

READ MORE: Lawyer says independence is 'bigger than any individual' after Murrell arrest

Separately, former Scottish cabinet secretary and SNP MSP Alex Neil also said there were questions for police to answer over the timing of the probe.

He told The Telegraph: “Police Scotland should make it clear if they were asked in any way to delay this arrest and, if so, why did they do so.

“They should be totally open and honest and let us know if in any way they changed the timing of this arrest because of the SNP leadership election.”

And former SNP depute leader Jim Sillars said the “public are asking questions that the police have to answer” such as whether the police investigation had “an effect on the date of the leadership election”.

Opposition figures have also said there are questions for the SNP to answer over the arrest, with Scottish Labour’s depute leader Jackie Baillie calling on “Humza Yousaf and Nicola Sturgeon to urgently state what they knew and when”.

There are whispers that some in the upper levels of the party may have known in advance that the police probe into the £600,000 raised for an indyref2 campaign was coming to a head. One source told the National they believed it was “highly likely” that the investigation played a role in Sturgeon’s decision to resign in February.

Police Scotland have said that neither Sturgeon nor Murrell were “notified in advance” of the arrest, but a spokesperson declined to answer when asked if anyone in the SNP had asked for the arrest to be delayed.

A spokesperson for the former first minister said on Wednesday that she'd had "no prior knowledge" of the arrest of her husband.

The force said in a statement on Wednesday evening: “A 58-year-old man who was arrested as a suspect earlier today in connection with the ongoing investigation into the funding and finances of the Scottish National Party has been released without charge pending further investigation.

“The man was questioned by Police Scotland detectives after he was arrested at 7.45am. He was released from custody at 6.57pm. Officers also carried out searches today at a number of addresses as part of the investigation. A report will be sent to the Crown Office and Procurator Fiscal Service.”