Nicola Sturgeon faces calls to resign after previously secret legal advice and new witness evidence raised fresh questions over whether Scotland’s first minister misled parliament about the Alex Salmond crisis. On Tuesday evening the Scottish government released confidential legal advice that showed its lawyers had warned Sturgeon and her most senior officials that evidence of a potentially unlawful conflict of interest inside the government was “extremely concerning” and a “very real problem indeed”. The alleged conflict of interest related to a government inquiry into harassment allegations made by junior female members of staff about Salmond, which he has denied. In a separate development, one of Salmond’s lawyers, Duncan Hamilton, told the Scottish parliament that Sturgeon had offered to intervene on Salmond’s behalf in a private meeting at her home on 2 April 2018. Hamilton told a Holyrood committee: “I can confirm that the first minister did offer to assist. We discussed mediation. My clear recollection is that her words were: ‘If it comes to it, I will intervene.’” Hamilton added that Sturgeon later withdrew that offer of help. The claims were released hours before Sturgeon testifies on oath to a Holyrood committee investigating the controversy in what is expected to be a marathon evidence session before MSPs from 9am on Wednesday. Sturgeon has repeatedly denied ever offering to help Salmond, and also insisted she did not know exactly why Salmond wanted to meet her on 2 April but thought he was considering resigning from the Scottish National party in protest at the government investigation. Douglas Ross, the Scottish Conservative leader, said the latest revelations made Sturgeon’s position untenable. “There is no longer any doubt that Nicola Sturgeon lied to the Scottish parliament and broke the ministerial code on numerous counts,” he said. Ross said the Scottish government’s legal advice showed the government and Sturgeon were also responsible for wasting public money by continuing the fight against Salmond’s legal action despite clear warnings from their lawyers they were likely to lose. “No first minister can be allowed to mislead the Scottish people and continue in office. [The] weight of the evidence is overwhelming. Nicola Sturgeon must resign.” Sturgeon’s chief spokesman said she had no intention of quitting. “To call a vote of no confidence in the middle of a pandemic, before hearing a single word of the first minister’s evidence, is utterly irresponsible. “It is for the public to decide who they want to govern Scotland and – while we continue to fight the Covid pandemic – with the election campaign starting in just 20 days, that is precisely what they will be able to do.” Other opposition parties did not immediately support Ross’s demands but kept the prospect of supporting them open. Jackie Baillie, the deputy leader of Scottish Labour and a member of the Holyrood committee, said the first minster “has serious questions to answer. She comes before the committee tomorrow and it is only fair to hear from her before coming to a conclusion” about whether she should quit. The government’s legal advice, from Roddy Dunlop QC, now dean of the Faculty of Advocates, was given to Scotland’s chief civil servant, Leslie Evans, on 31 October and 6 December 2018. It is thought that was then shared with Sturgeon, but the government did not decide to concede Salmond’s legal action until 31 December. In another set of potentially damaging disclosures, two allies of Salmond stated in writing that one of his former aides, Geoff Aberdein, had told them in early March 2018 the name of a complainer against Salmond had been leaked to him. Hamilton, a respected advocate and one of Salmond’s lawyers, told the committee that Aberdein gave him the name of a complainer against Salmond in early March 2018 after it had been given to him by a “senior government official”. Kevin Pringle, formerly a special adviser when Salmond was first minister and an SNP official, who took part in that conference call with Hamilton and Aberdein, told MSPs investigating the crisis that Aberdein “is in no doubt that a complainant’s name was shared with him”. Hamilton also supported Salmond’s evidence under oath last Friday that Sturgeon had wrongly told the Scottish parliament in 2019 that she had no advance knowledge of why she was meeting Salmond at her home on 2 April. Salmond told the committee a meeting had been arranged between Sturgeon and Aberdein for 29 March 2018 in her Holyrood office, with the express purpose of setting up that meeting between Salmond and Sturgeon at her home four days later. Hamilton and Aberdein were invited to that meeting on 2 April, Salmond said. Hamilton told the committee: “I can confirm that statement is correct.” He said neither he nor Salmond would ever have turned up at Sturgeon’s home without an invitation from her. The meeting was to discuss the Scottish government’s internal investigation into allegations of sexual assault against Salmond. “Everyone in the room knew exactly why we were there,” Hamilton said. “No introduction to the subject was needed and no one was in any doubt what we were there to discuss.” John Swinney, the deputy first minister, who is the minister in charge of handling the Salmond controversy, had previously refused to release this legal advice despite losing two votes in the Scottish parliament last year. But all four opposition parties said on Monday they would back a Tory no confidence motion tabled against Swinney if he failed a third time to release the legal advice in full. The Tories said on Tuesday they were pressing ahead with that vote. The documents show that Dunlop and his junior, Christine O’Neill, warned Evans on 6 December that the disclosure that a government official had spoken to both complainers before they made complaints and before that official was made investigating officer, meant Salmond’s legal challenge would “more likely than not succeed”. They stated: “This is, we regret to advise, a substantial problem.” They warned the investigating officer’s appointment was likely to be unlawful. The Scottish government’s harassment policy had stated any investigating officer “will have had no prior involvement with any aspect of the matter being raised”. The documents also reveal that on 31 October 2018, two months before the Scottish government’s chief civil servant decided to concede the case on 31 December, Dunlop warned them the disclosure the investigating officer had previously spoken to the complainers presents “a very real problem indeed”. He added: “It would be wrong for me to suggest that this revelation is anything other than an extremely concerning one.”