The SNP has refused to suspend its former chief executive following his arrest last week as part of probe into the party's finances.
Peter Murrell, who is also the husband of former First Minister Nicola Sturgeon, is thought to have retained his membership.
It comes despite police having carried out a two day search of the influential Scotsman's home, seizing a luxury campervan from outside his 92-year-old mother’s house, and having been questioned by police for 12 hours last Wednesday.
He was released without charge, pending further investigation.
Peter Murrell was released without charge after police raided his house
PAPolice are examining what happened to £600,000 in funding that appears to have gone missing.
Despite the investigation overshadowing the SNP, party insiders say that it is up for Murrell to decide for himself whether to "step away".
"Any decision to ‘step away’ from membership during the investigation would be for him," one person with knowledge told The Telegraph.
Sources highlighted that he had not been charged by police and that his membership should not be given extra scrutiny now that he had resigned as chief executive.
Murrell quit his role overseeing the party last month after he inaccurately briefed detail to the media about the SNP's membership numbers.
The 58-year-old had rejected suggestions 30,000 people had left the party before being later forced to admit the figure.
As well as Murrell remaining a party member, there is thought to be anger among SNP Members of the Scottish Parliament that central funding could be used to help pay for the former chief executive's legal defence.
New Scottish First Minister Humza Yousaf warned over the weekend that the party may have "obligations" to cover the legal costs of Murrell's defence, given that the police investigation relates to when he was directly employed by the SNP.
Several MSPs are claimed to now be threatening to withhold their £250-a-month membership subscriptions in protest.
The SNP is thought to have hired leading lawyer Stuart Munro who specialises in "allegations of financial crime" to advise on the current situation.
Ian Blackford has urged the party to come together
PA
Former Westminster leader, Ian Blackford has appealed for MPs and MSPs to stick together through the difficult period.
"I would appeal to everyone in the party to come together now the election contest for the leader and the First Minister is over," Blackford said.
"I’m optimistic but we need to make sure that we show that we’re worthy of the support of the people of Scotland."
He added: "We need to demonstrate that we are worthy of the trust of the people and it’s about, I would say, the Scottish Government delivering across all the devolved areas and doing the work that we need to do to demonstrate that the best answer for Scotland is to become an independent country."
