Massachusetts formally dropped more than 21,000 tainted drug convictions Thursday that were linked to a disgraced state chemist who in 2013 admitted to faking test results.
It's the largest single dismissal of convictions in U.S. history, according to the American Civil Liberties Union.
Thursday's dismissals by the Massachusetts Supreme Judicial Court had been expected after several district attorneys on Tuesday submitted lists of 21,587 cases they said they would be unwilling or unable to prosecute, The Associated Press reports.
Over the nine years Annie Dookhan worked at the Hinton State Laboratory Institute outside Boston, she admitted to returning positive results on drug evidence she never tested and to sometimes forging co-workers' signatures.
As the scandal unfolded, hundreds of people were released from prison and hundreds more had their charges dismissed.