Scotland Yard is to publish a report into the death of anti-racism activist Blair Peach more than three decades ago.
Relatives of the dead man have been campaigning to obtain a secret internal review of the killing for many years.
Last year Metropolitan Police Commissioner Sir Paul Stephenson said he was willing to publish the document but only after it had been checked by solicitors.
The report will finally be made public after the Crown Prosecution Service said on Friday that officials have completed their work and given their findings back to senior officers.
It is understood that a copy of the report has already been passed to solicitors representing Mr Peach's partner Celia Stubbs.
The decision to publish was made after public pressure to reveal the almost forgotten review in the months after the death of Ian Tomlinson during G20 protests. But police solicitors advised prosecutors should look at it in case there is any chance further inquiries could be made and charges brought.
Mr Peach, 33, was hit over the head at a demonstration against the National Front in Southall, west London, in 1979. Members of the Met's riot squad, called the Special Patrol Group, were suspected of hitting him with a rubberised police radio or a lead-filled cosh.
The report written by Commander John Cass, a former senior officer at the Met's internal complaints department, examined his death. He is believed to have recommended the prosecution of police officers although no charges were ever brought.
Ms Stubbs' solicitor Raju Bhatt said she and the family wanted a public acknowledgement of the police's responsibility for Mr Peach's death.
He told BBC Radio 4's Today programme: "The question of a prosecution is beside the point. What has been clear from the evidence is that Blair Peach died as a result of a blow struck by a police officer and the public acknowledgement of that fact is awaited by the family from the Metropolitan Police and the authorities generally. It would mean a clear step forward. It would mean the Metropolitan Police had finally addressed the weight of the evidence facing them."
