“I am proud of my 16 years of working for the people of Massachusetts. I disagree with the Court’s decision and the characterization of my conduct in this case,” said Kaczmarek.

Foster is now general counsel at the Massachusetts Alcoholic Beverages Control Commission. She did not respond to a request for comment.

“The nature and scope of governmental misconduct by Kaczmarek and Foster in withholding evidence was severe,” Carey wrote. “It continued for a prolonged period, in violation of many drug lab defendants’ constitutional rights.”

Kaczmarek, who led Farak’s prosecution and also prosecuted former state chemist Annie Dookhan, cited these work sheets in memos to her supervisors. She also provided copies to Farak’s defense attorney, but not to the Hampden District Attorney’s Office, which was responsible for passing along pertinent evidence to defendants.

In response to motions from defense attorneys, Foster told a judge that all relevant materials had already been turned over, characterizing such motions as a “fishing expedition.” Foster later testified that she never actually reviewed the evidence files to determine what had not been turned over, and that she intentionally wrote a “vague” letter to the judge to avoid representing that she had.

Carey found that the two prosecutors “managed to withhold the mental health worksheets through deception.” He rejected Kaczmarek’s explanation that she forgot about the work sheets, and deemed Foster’s actions “inexcusable.”

In March, the state attorney general’s office acknowledged that both prosecutors made mistakes, but argued that they were not severe enough to warrant throwing out convictions. But Carey determined that the circumstances demanded that the cases be dismissed in order to deter misconduct by prosecutors in the future.

“The ramifications from their misconduct are nothing short of systemic,” Carey wrote. “Had the AGO made timely disclosures of the mental health worksheets, many of the defendants before me now . . . would not have spent as much time incarcerated.”

Attorneys for the defendants welcomed the ruling.

“In not turning over this vital evidence, the attorney general ensured that a scandal would devolve into a travesty of justice,” said Springfield-based lawyer Jared Olanoff.

“Judge Carey did brilliant, fearless work concerning the misconduct committed by the prosecutors who intentionally withheld exculpatory evidence,” said attorney James McKenna.

The attorney general’s office is reviewing the decision, according to spokeswoman Emalie Gainey.

Shawn Musgrave can be reached at shawnmusgrave@gmail.com. Reporting for this story was supported by the Fund for Investigative Journalism.