Medical staff called for the removal of leg restraints and handcuffs when dying Sheku Bayoh arrived in hospital.
The revelation came as the Kirkcaldy man who died in police custody five weeks ago was buried on Sunday.
Representing the heartbroken family, solicitor Aamer Anwar said there were many questions raised about the events which unfolded that day and that the family would not rest until the truth emerged.
To audible shock from those who had gathered to pay their last respects, he said: “We know when Sheku Bayoh arrived at hospital unconscious he still was handcuffed and leg restraints were still in place. Doctors demanded their removal.”
Criticising a portrayal of Sheku as a powerful and large man of “extraordinary strength”, he said the negative imagery was deliberately used to reinforce an image of a dangerous man.
He also rejected claims there was a lone police officer first on the scene that morning, saying the female police officer injured was one of a team of four.
This is the most serious case to come before the Police Investigations Review Commissioner (PIRC) since it was set up in 2013.
But Mr Anwar raised questions about a “fundamental weakness” in the powers of the investigating body.
Speaking on behalf of the family, he said there was a “dangerous situation” in which its powers “disappear” when investigating the most serious cases, when looking into a death in custody.
“We need to resolve this flaw so it doesn’t happen to another family again,” he said.Click here for a full photo galleryIt came as the PIRC said it had tried several times to secure statements from the officers involved, despite Professor Peter Watson, the Scottish Police Federation’s legal adviser, stating officers had only been asked for interview last week.
“The fact is, for 32 days they refused to provide this information. The fact PIRC could do nothing about it beggars belief and compounds the agony of the family,” he said.
Professor Peter Watson, of PBW Law, who represent the police officers involved, last night issued a statement in which he said: “Everyone acknowledges that this is an extremely serious incident and requires investigation.
“The police officers involved, including the female officer who was attacked, have been happy to cooperate from the outset but it was the responsibility of PIRC to declare the officers’ status and that is a basic legal requirement. This was officially confirmed on June 2.”
Concerns over the powers open to the PIRC in such serious cases has led for a call for cross-party support at Holyrood to back a change in the law, making it mandatory for officers to provide operational statements on their return to their station after a death in custody.
“Why should it be powerless when it comes to a death in custody?” Mr Anwar said.