More than 40 years after America's bloodiest prison rebellion, newly-released documents contain accounts saying injured inmates were beaten with clubs and others had torture wounds as state police and guards retook control of the jail.
Three inmates and one guard died at the hands of prisoners in the riot and siege at the maximum-security jail in Attica, New York, that ended on September 13 1971.
The 1,300 prisoners who rioted over conditions and controlled part of the jail had clubs, knives and makeshift weapons and threatened to kill hostages. State police and guards shot dead 29 inmates and 10 hostages when they stormed the prison after negotiations stalled.
The documents, released two years after New York state attorney general Eric Schneiderman sought the disclosure, say several witnesses to brutal crimes against prisoners were not contacted or interviewed by criminal investigators.
They show apparent violent crimes by authorities, described by neutral witnesses, after the shootings and the surrender of 1,300 inmates following the riot and five-day stand-off at the prison.
Such abuses have long been alleged by prisoners and their families, and the newly-released witness accounts lend credence to their arguments.
A 1975 report by Judge Bernard Meyer concluded there was no intentional cover-up, only serious errors in judgment and omissions in evidence gathered by troopers. He also noted an imbalance in the ensuing prosecution - more than 60 prisoners but just one state trooper were indicted.
That conclusion, contained in the 570-page report's first volume, has been public for 40 years. The 46 pages detailing some of the factual basis for Judge Meyer's findings were released yesterday. Another 350 pages remain sealed because they contained grand jury evidence, which by law is generally kept secret to protect the privacy of witnesses and investigation targets.
A judge refused last year to make an exception to release those pages for the public and historical Attica record.
"Today, we are shining a light on one of the darkest chapters of our history," said Marty Mack, executive deputy state attorney general. He said this release might bring families of the victims nearer to closure and help Americans learn from what happened.
But Michael Smith, a corrections officer taken hostage in the riot and shot when the prison was stormed by police, said so much was redacted there was not much new, and significant information was still being suppressed.
"The truth will all come out some day but I don't know if anybody's going to be alive who was involved in the event," he said.
In the newly-released details, Judge Meyer wrote that his own public request for information led to contacts and interviews that were made available to the criminal investigators but apparently went unused. The judge, who later sat for seven years on New York's highest court, died in 2005.
"A National Guardsman who treated wounded inmates only to have bandages ripped off, saw stretchers deliberately tilted, saw guards beat inmates on medical carts with clubs, saw a prison doctor pull an inmate off a cart and kick him in the stomach, saw inmates beaten while running a gauntlet," he wrote.
The criminal investigation files contained no record of the guardsman or any attempt to interview him, he noted.
A doctor saw "an inmate with large wounds around his rectum which were not from gunshot", which the doctor later heard were caused by a broken bottle, Judge Meyer wrote. The doctor also said he was refused permission to take a brain-damaged inmate to the hospital and a day later saw prisoners with untreated broken bones.
Another guardsman gave evidence in a federal class-action suit by inmates that he saw "inmates beaten on stretchers, poked in the groin and rectum with nightsticks, beaten while running through gauntlets", Judge Meyer wrote. Other inmates and observers gave evidence about cigarette burns on prisoners.