In a scathing critique of many of the 11 officers who arrested Roberto Laudisio Curti in the early hours of March 18, the NSW Coroner, Mary Jerram, said they acted like "schoolboys in Lord of the Flies", with no idea what the problem was, or what threat or crime was supposedly being averted by the chaotic and violent struggle.

Mr Curti was tasered multiple times and sprayed with OC spray.

"The actions of a number of the officers were ... reckless, careless, dangerous and excessively forceful," she said.

"They were an abuse of police powers [and] in some instances even thuggish. Roberto's only foes during his ordeal were the police ... Certainly, he had taken an illicit drug, as has become all too common in today's society. But he was guilty of no serious offence. He was proffering no threat to anyone."

Ms Jerram handed down 35 pages of findings in Glebe Coroner's Court on Wednesday morning following a two-week inquest into the death of the 21-year-old Brazilian student and football player.

While stopping short of recommending criminal charges, Ms Jerram delivered a damning indictment on the entire episode. "It's impossible to believe that he would have died but for the actions of police," she said.

Mr Curti was chased by police down Pitt Street, tasered several times, sprayed with almost three cans of OC spray, handcuffed and restrained by seven officers on the ground.

He had earlier jumped the counter of a convenience store in a paranoid, LSD-induced psychotic state and taken two packets of biscuits. It was reported over police radio as an armed robbery.

Ms Jerram said many officers had lied to the inquest and "conveniently forgotten" evidence.

She said the most senior officer present during the violent struggle on Pitt St, Inspector Gregory Cooper, gave evidence that was so conflicting and self-serving it "hardly deserves narration".

He claimed that he told the junior officers to stop using their Tasers. None of those officers heard the order and the Coroner said it was likely he never made it but was seeking to shift the blame onto other officers in court.

Ms Jerram suspected that some officers were angry and emotional because they had been hit by Taser shots and inadvertently sprayed during the botched arrest.

However she said it was not right to refer them for criminal charges as it was about "policing issues warranting investigation by policing bodies".

Ms Jerram recommended five officers, including Probationary Constable Daniel Barling, who tasered Mr Curti five times after he was handcuffed, be disciplined.

She also called for an immediate review of the vague and confusing standard operating procedures relating to the use of OC spray, Tasers, handcuffs, restraint and positional asphyxia, particularly the use of multiple taser shots and its "drive stun mode" as a pain compliance tool.