SECRET police files linked to the first fatality of the troubles will be not be released until at least 50 years after the death.
Father-of-nine Sammy Devenny (43) died in July 1969, three months after suffering severe head injuries when he was attacked by RUC officers in his Derry home.
No-one was ever prosecuted. Immediately after Mr Devenny's death, an inquiry was ordered by the then head of the RUC, Sir Arthur Young.
He brought in London Metropolitan Police superintendent Kenneth Drury to investigate.
In his report -- which was not released until 2001 -- Supt Drury criticised RUC officers for failing to cooperate with him.
"I am satisfied that amongst those officers, who possess this guilty knowledge, there is a conspiracy of silence motivated by a misconceived and improper sense of loyalist to their guilty comrades," he said.
Derry-based human rights' group the Pat Finucane centre (PFC)
has now revealed that two files relating to Mr Devenny's death have been re-classified as secret and will not be made public until at least 2022. Two years ago the Metropolitan Police force ordered the files be retained for another 10 years. The PFC sought access through a Freedom of Information request but was turned down "in the public interest".
Mr Devenny's daughter, Christine Robson, said it was reasonable to assume the files held information which was damaging to the RUC.
"It is incredible that a man can be attacked in his home by police, in front of his family, and no-one is held to account," she said.