In 1971, more than 1,000 prisoners overwhelmed guards and employees, holding hostages in the uprising. Over 40 men died, both inmates and prison staff.
Democrat and Chronicle reporter Gary Craig spoke to us about the decision to release the documents.
"These reports were an investigation into whether there was a cover up of police activity when they retook the prison and whether people were fatally shot on purpose or accidentally," he said. "There were some claims of a state prosecutor covering it up. The determination was the investigation was lousy."
The documents remained sealed all this time due to a judicial grand order.
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