The verdict came with three riders: that there should be more control of the Special Patrol Group (SPG) police unit by officers, that there should be better liaison with local police, and that no unauthorised weapons should be available in police stations.
Mr Peach’s supporters greeted the jury’s conclusion with dismay.
At a news conference, Mr Peach’s girlfriend, Celia Stubbs, said the policeman who killed him had got off “scot-free”.
We regard the verdict as establishing beyond any doubt that police killed Blair Peach, Paul Holborow, Anti-Nazi League
The Anti-Nazi League, which organised the demonstration in which Mr Peach was killed, said it would seek to have the verdict overturned.
The League’s National Secretary, Paul Holborow, said, “We regard the verdict as establishing beyond any doubt that police killed Blair Peach.
“We think that the riders indicate that the SPG is an uncontrolled private army and has a licence to kill.”
The verdict was welcomed, however, by Police Federation chairman James Jardine, who added that he hoped the matter would end there.
Blair Peach, a 33-year-old schoolteacher from New Zealand, died of fatal head injuries at an Anti-Nazi League protest against a National Front meeting at Southall on 23 April last year.
His inquest has become one of the longest in legal history, with 84 witnesses going before the court.
They included the 40 SPG officers implicated in the incident.
None of the police witnesses admitted hitting Mr Peach, although three said they saw him sitting on the pavement.
During the hearing it emerged that there had been an internal investigation into the death by a team of 30 detectives led by Commander John Cass of Scotland Yard’s Complaints Investigation Bureau.
The jury heard how items such as crowbars, sledgehammers and coshes were found in the lockers of members of the SPG.
However, the coroner twice refused to admit the investigation report as evidence, leading to accusations of a cover-up by the Anti-Nazi League.