Annie Dookhan, a former chemist at the Hinton State Laboratory Institute, during her arraignment at Brockton Superior Court in Brockton, Massachusetts, on Jan. 30, 2013. REUTERS/Jessica Rinaldi Massachusetts' top court will on Thursday consider arguments on how to handle tens of thousands of drug convictions that were potentially tainted by a rogue crime-lab scientist, in a case that could have national implications.

The American Civil Liberties Union and the law firm Foley Hoag will argue at the Massachusetts Supreme Judicial Court for measures to speed up reviews of the cases and to limit the powers of prosecutors to oppose them.

"People who have suffered ... are being scared away from challenging their wrongful convictions by the threat of even harsher punishments," Foley Hoag partner Daniel Marx said in a statement before the hearing.

Former crime lab scientist Annie Dookhan pleaded guilty in 2013 to tampering with evidence at the now-closed Hinton State Laboratory Institute in Boston, where she worked from 2002 to 2011. She is serving a three-to-five-year jail sentence.

Investigators have said her mishandling of evidence may have tainted cases involving as many as 40,000 people, shaking the foundations of the state's criminal justice system. More than 300 people convicted of drug violations have been released from prison as a result, and many others are seeking retrials.

Dookhan also testified in about 150 criminal cases since 2009 while claiming false credentials.

"I screwed up big time," Dookhan said, according to the report by investigators for Attorney General Martha Coakley's office obtained by the Associated Press. "I messed up bad. It's my fault. I don't want the lab to get in trouble."

The AP also reports that supervisors at the Boston lab, which was closed by police in August 2012, may face federal scrutiny because they did not intervene after lab employees reported concerns about Dookhan's work.

"I can't imagine she could have been this corrupt without someone noticing," attorney Rosemary Scapicchio, who represents several defendants whose samples Dookhan handled, told the AP. "The investigation needs to go deeper than Annie Dookhan to get to the point of 'How did she get away with it?'"

The Supreme Judicial Court ruled last year that the state shared blame for Dookhan's misconduct and that the court could mull a "systemic approach" to addressing the aftermath.

Any decision by the court deriving from Thursday's hearing could set a national precedent on how to handle convictions that were based on evidence from crime labs later found to have flawed practices.

The Massachusetts Inspector General said the state ignored warning signs throughout Dookhan's tenure, including the fact that in the first two years on the job she tested more than 8,000 samples a year, more than double her next-most productive colleague.

(Reuters reporting by Richard Valdmanis.)