BOSTON — Prosecutors have identified at least 6,000 cases impacted by a former chemist who authorities say was high almost every day for eight years while she worked at a state drug lab, officials said Tuesday.

Numbers provided by district attorneys’ offices during a hearing at Massachusetts’ highest court provide the clearest picture to date about the potential impact of chemist Sonja Farak’s misconduct.

The American Civil Liberties Union of Massachusetts and the state’s public defender agency, who are urging the Supreme Judicial Court to dismiss all the cases, have blasted prosecutors for not providing a comprehensive list of affected defendants.

“We had to wait nearly five years and file this lawsuit just to hear there are at least 6,000 people affected,” Matthew Segal, legal director of the ACLU of Massachusetts, said after the hearing. “When were those people going to receive a letter from the Commonwealth if we didn’t file this lawsuit?” he asked.

The ACLU and Committee for Public Counsel Services filed a petition with the court in September asking the justices to throw out all convictions tied to evidence handled by Farak, who worked at the lab between 2005 and 2013.

Farak pleaded guilty in 2014 to stealing drugs from the state crime lab at the University of Massachusetts Amherst and was sentenced to 18 months behind bars.

Assistant Hampden County District Attorney Bethany Lynch told Justice Frank Gaziano that it has identified about 4,300 Farak cases and is working to determine which cases it will agree to dismiss and which ones it wants to retry.

Meanwhile, officials from Berkshire, Middlesex, Northwestern and Worcester district attorneys’ offices said they’ve identified more than 2,000 Farak cases combined.

The total number of affected cases statewide is almost certainly higher, because several other prosecutors who attended Tuesday’s hearing did not say how many they’ve found.

A trial judge earlier this year dismissed the convictions of several defendants whose cases were handled by Farak. The judge also found that two former assistant attorneys general “tampered with the fair administration of justice” by withholding evidence about the scope of Farak’s misconduct.

Farak’s case is separate from another Massachusetts drug lab scandal that resulted in the dismissal some 21,000 convictions this year.

Those cases were tossed because of misconduct by Annie Dookhan, a chemist at the William A. Hinton State Laboratory in Boston, who was accused in 2012 of falsifying drug tests. She was later sentenced to three years in prison after pleading guilty to obstruction of justice, perjury and tampering with evidence.


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