District Attorney Todd Spitzer made the decisions after his office and the Sheriff's Department jointly reviewed more than 22,000 cases that led to convictions, a statement from the DA's office said.
"Due process is the cornerstone of our criminal justice system and is embedded within our federal and state constitutions," said a report from the DA's office. "The collection and preservation of evidence is a key element of procedural due process."
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The DA's became involved after learning that internal Sheriff's Department audits had found widespread problems with deputies booking evidence late or not at all, including methamphetamine and weapons, authorities said.
The cases reviewed covered a three-year period that ended in March 2018 during the tenure of former District Attorney Anthony Rackauckas, whom Spitzer defeated in a 2018 election.
Thousands of defense attorneys were notified of the evidence problems that were found and Spitzer also removed genetic samples from a county DNA database for all defendants in cases that were reviewed, whether or not there was any actual booking problem, according to the DA's office.