The Sheku Bayoh Inquiry chairman wrote to grieving relatives to say he was "humbled and honoured" to hear their experiences - sparking calls for him to step down over concerns of bias following five meetings described as "secret", the inquiry has heard.
Father-of-two Sheku Bayoh, 31, died after he was restrained by around six police officers in Kirkcaldy, Fife, in 2015.
The Crown Office decided not to take legal action against the officers involved following an investigation, but the circumstances are being examined at the inquiry.
A two-day procedural hearing, beginning on Thursday, was ordered by chairman Lord Bracadale to consider an application for his own recusal, after he revealed he has met with Mr Bayoh's family on five occasions since the inquiry began.
The application was made by the Scottish Police Federation, PC Craig Walker and former officer Nicole Short, represented by Roddy Dunlop KC, dean of the Faculty of Advocates.
Recusal is the legal process by which a judge or other adjudicator steps aside from participating in a case due to potential bias, conflict of interest, or lack of impartiality.
Mr Dunlop said Lord Bracadale had written he was "humbled and honoured" to hear the family's experiences, and that the chairman had identified two instances of "inappropriate" comments, including by the family's solicitor, Aamer Anwar.
The inquiry heard a relative made a comment that the arrest "should never have happened", according to Mr Dunlop, while in another meeting it was alleged the family "are the victims", which was rejected by Mr Dunlop who said there was a serious factual dispute at the centre of the inquiry.
The meetings occurred on 4 November 2021; 13 April 2022; 21 November 2022; 18 January 2024; and 5 December 2024.
Mr Dunlop said: "There is an acute dispute into who is the villain in this piece."
He said the family had portrayed Mr Bayoh as "Scotland's George Floyd", but added: "This is a man who was intoxicated and armed with a knife.
"If I had approached Your Lordship and said, Nicole Short wants to tell you in private how devastating was the illegal assault perpetrated upon her by Mr Bayoh, which ended her career with the police, Your Lordship would have instantly dismissed me, and quite rightly, he would have been entitled to raise a complaint as to my conduct."
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Dan Byrne KC, representing three officers involved in the inquiry, said they had told him: "The chair has no idea who we are, we are just white officers."
He told the inquiry "repeated private, secret meetings with one party, behind the back of the others", did not comply with a statutory requirement to act fairly.
Mr Byrne said: "The treatment they say is a parallel to George Floyd, by convicted murderer Derek Chauvin. That's clear from the campaign.
"The purpose of influence is the prosecution of the officers. The advocacy is explicit and implicit. The officers do not have a campaign group, they do not have access to the media or senior judges.
"In my submission the meetings were private, they were not transparent, there was no disclosure. The officers simply would not have had these chances.
"In the central dispute, the family have now had considerable advantage. The chair knows them personally; but no-one knows the officers, their families, their values, they have a great deal to lose."
The Crown Office and Solicitor General Ruth Charteris KC do not support the calls for recusal.
Mark Moir KC, representing the Coalition for Racial Equality and Rights, said it is "a relatively common feature of a public inquiry" for the chair to meet families involved, as he rejected calls for Lord Bracadale to step down.
Acting for the family, Claire Mitchell KC said chairs of other inquiries, including the Victoria Climbie Inquiry, the Grenfell Tower Inquiry, the Stephen Lawrence Inquiry, and both COVID-19 inquiries, had met with families involved.
She said: "Chairs meet with family members on a regular basis and that is something which has been endorsed."
Lord Bracadale said he will "take time" to consider the submissions and will "return in due course".