Alex Salmond had not spoken publicly for almost a year, since the day he was acquitted of all 13 sex assault charges last March.
Keeping quiet, the former First Minister acknowledged in his opening remarks, had not "hitherto been my normal policy". "I said nothing... today, that changes," he said.
Over the next six hours, he set out a series of remarkable claims about what he described as a "malicious plan" against him, which he alleges was launched by his former SNP allies.
Mr Salmond has said he has evidence showing that senior figures in the SNP, including Nicola Sturgeon's husband, put pressure on and colluded with witnesses and "constructed evidence" against him.
The 66-year-old said that, when he read a tranche of messages from senior party and Scottish government figures – turned over to him as part of the disclosure process in his criminal trial – it was one of the most "extraordinary" and "distressing" days of his life.
He has been threatened with prosecution if he publishes them. However, while the witness session was ongoing, it was confirmed that a new legal order had been issued to the Crown Office to access the messages by the parliamentary committee. Mr Salmond suggested that, if a legal order was served on his lawyers, he would quickly comply.
Some messages have leaked into the public domain, including one from Peter Murrell, Ms Sturgeon's husband and the SNP chief executive, who spoke of applying pressure to police about the Salmond affair.
Mr Murrell has claimed the messages were "out of character", had been misinterpreted, and that he had sent them because he was upset. However, Mr Salmond said there "many other messages and what they speak to is behaviour that I would never have countenanced from people I had known in some cases for 30 years".
He added: "In my opinion there has been behaviour that has been not just about pressuring police, but pressuring witnesses, collusion with witnesses, we're talking about the construction of evidence because the police somehow were thought to be inadequate in finding it themselves."
Mr Salmond has alleged that figures including Mr Murrell, Sue Ruddick, the SNP's chief operating officer, Liz Lloyd, Ms Sturgeon's chief of staff, and Ian McCann, the party's compliance officer, were involved in a "deliberate, prolonged, malicious and concerted effort" to damage his reputation and have him jailed.
The April 2018 meeting
One of the main charges facing Ms Sturgeon is that she lied to Holyrood about when she became aware that her predecessor was being investigated for sexual misconduct.
She had told MSPs, as well as Scotland's top court, that the first time she became aware of the probe was on April 2, 2018, when Mr Salmond visited her at her Glasgow home to tell her about it. But Mr Salmond says he knows for certain that Ms Sturgeon knew about it on at least March 29, 2018, as it was discussed at a meeting at her Holyrood office with his former chief of staff Geoff Aberdein.
Ms Sturgeon has claimed she "forgot" about the earlier meeting and has suggested it was opportunistic and casual. However, Mr Salmond said it was a formal meeting and had been explicitly set up to talk about the investigation he faced.
"The purpose of the meeting was to brief Nicola on what was happening and to make sure the meeting on the second of April was taking place," he said. "I know that Nicola Sturgeon knew about the complaints process at the meeting on the 29th of March because I was told so by Geoff Aberdein, who told her at a meeting arranged for that purpose.
"Whether she had any prior knowledge of it I cannot say, but I know she knew about it on the 29th of March."
Ms Sturgeon has denied misleading parliament, but her claim of forgetting the March 2018 meeting is seen as one of the major holes in her story. She is sure to be asked about it when she appears before the committee next week.
Under the ministerial code, any minister who knowingly misleads parliament is expected to resign, with opponents believing the controversy about what she knew and when could end her political career.
Ms Sturgeon also faces claims that she broke the code by failing to record the meetings in her ministerial diaries.
The actions of Scotland's prosecution service – the equivalent of the Crown Prosecution Service in England – came in for particularly harsh criticism from Mr Salmond, who called for the Law Advocate, Scotland's top law officer, to resign.
In a remarkable submission highlighting his concern over the strength and conduct of Scottish institutions, he said that while he wanted Scotland to be independent he also wanted it to be somewhere with robust safeguards, where citizens were not subject to "arbitrary authority".
He revealed that he had been threatened by the Crown Office to limit the scope of his evidence and not to speak about sections of his written submission already in the public domain.
The body came in for major criticism this week when it put pressure on the Scottish Parliament to delete sections of Mr Salmond's written evidence, which it complied with.
The former First Minister said: "The idea the only place [my evidence] can't be discussed is in a parliamentary committee is the direct opposite of what should be true. Parliamentary committees should actually be able to discuss things that cannot be discussed elsewhere, because of proper exercise of parliamentary privilege and the duties of members of parliament.
"It seems to be an extraordinary position and clearly something is wrong, whether it's institutional or whether is personnel, as I suggest, is a matter for the parliament to decide but clearly, it's an intolerable situation and should not be allowed to continue."
He also accused the Crown Office of misusing legislation passed by his government to further block the provision of evidence. He said the provision it relied upon "was not passed by the parliament to prevent a parliamentary inquiry, getting to the truth on matters of the utmost public interest is being misused in its current context".
He added: "The application of these provisions and the threat of prosecution if I offer that evidence is in my estimation both extraordinary and unwarranted."
One of the committee's main tasks is looking at the circumstances around the judicial review Mr Salmond brought against the Government he once led.
Mr Salmond won the case, with a judge ruling that the civil service probe into two complaints against him had been "tainted by apparent bias". He was awarded more than £500,000 in legal costs, a bill met by the taxpayer.
He claimed he knew the government had been told it was likely to lose the case months before it eventually conceded. A failure to heed legal advice is another ground on which he alleges Ms Sturgeon broke the ministerial code.
He also alleged that the Scottish government – knowing its case was in trouble – had deliberately sought to delay his civil case so that it could be paused and overtaken by the criminal investigation. He believes this was one of the motivations senior SNP figures had in seeking to promote a criminal case against him.
Ms Salmond said: "The description that is most commonly made in the press about the government's policy and what happened is 'botched'. Your committee is examining, as is often said, the 'botched policy'. The policy wasn't botched. The policy was unlawful, unfair and tainted by apparent bias. Botched doesn't cover it."
Mr Salmond was investigated under a new policy, drawn up by the Scottish government in the wake of the MeToo movement. For the first time, it allowed former ministers to be investigated. Allies of the former First Minister have claimed the policy was specifically designed to "get" him – something Ms Sturgeon and Leslie Evans, her chief mandarin, have always denied.
Asked whether he accepted that the MeToo movement was the genesis of the procedure, he said: "I think it would be difficult to understand why out of the MeToo movement, and the range of huge issues that were discussed in parliament, if anyone thought or believed that out of that what you absolutely required was a policy on former ministers, that strikes me as very, very difficult to believe."
Mr Salmond alleged that the identity of a woman who accused him of sexual assault was passed to his former chief of staff by the Scottish government. He said the woman's identity was shared with Geoff Aberdein, who then passed the information to him.
The allegation is significant because, as recently as Wednesday, Ms Sturgeon denied the claim at First Minister's Questions. However, Mr Salmond said that he could corroborate the allegation as "three other people know that to be true."
Jackie Baillie, a Labour member of the committee conducting the inquiry, said it had written to the three people for their version of events.
Mr Salmond also argued there should be a "further police investigation" into a leak to the Daily Record newspaper about complaints against him.
He described how he was contacted on Aug 23, 2018, by the Scottish government to inform him that a press statement would be issued at 5pm that day confirming the existence of an investigation into sexual misconduct complaints.
This plan was withdrawn after he threatened to apply to the courts for an interdict preventing the disclosure, Mr Salmond told the committee. However, he said he was contacted by the Scottish government at 4pm to warn him that the Daily Record had got wind of the investigation, and at 8pm the newspaper asked him for comment.
Mr Salmond said the paper published a story the following day that included the same language as the permanent secretary's report on the inquiry and argued it was clear it had either been passed the full document or an extract.
A subsequent investigation by the Information Commissioner was "sympathetic" to the view that the criminal leak came from the Scottish government, he said.
Mr Salmond insisted: "Whoever did that [leaked the story] should answer for what is a very, very serious matter which caused enormous distress and the implications that followed."