CAMBRIDGE, Massachusetts A Massachusetts grand jury on Monday indicted a former state crime lab chemist on 24 new charges linked to allegations she falsified evidence while handling drug samples tied to more than 34,000 cases at the lab.
Annie Dookhan, 34, was arrested in September and investigators said last month they had identified 10,000 people convicted or accused of crimes based on evidence she had handled.
State officials said 236 people have been released from prison pending new trials as a result of the investigation.
Prosecutors said she tampered with drug evidence and faked test results at the Hinton State Laboratory Institute in Boston, where she had worked for nine years. She got the job, they charge, by falsely claiming she had a master's degree in chemistry from the University of Massachusetts.
"Her alleged actions have sent ripple effects throughout the criminal justice system," said Massachusetts Attorney General Martha Coakley, in a statement on Monday. "We are committed to working with all stakeholders to fix this situation and restore trust in the criminal justice system."
The release of prisoners convicted as a result of evidence Dookhan handled has created a headache for state and local officials. Boston Mayor Thomas Menino last month asked for $15 million in state aid to help the city cope with additional police and shelter expenses that resulted from the release.
The new charges include obstruction of justice, tampering with evidence and perjury, the statement said. She had previously been charged with obstruction of justice and falsely claiming to have an advanced degree in chemistry.
The grand jury's action follows Dookhan's arrest in September, when she was charged with obstructing justice and lying about her training. She pleaded not guilty to those initial charges and was released on $10,000 bail.
Dookhan, who told officials according to a police report that she "screwed up big time," has said that no one else at the lab knew what she had done and that she was just trying to get more work done.
She is due to be arraigned on the latest charges on Thursday.
Dookhan allegedly altered substances in vials to cover up her practice of "dry labbing," or visually identifying samples without doing the proper chemical testing, the statement said.
Authorities believe she gathered samples from different cases that appeared to contain the same substance, but tested only a few of them. She allegedly tampered with vials undergoing subsequent testing to make sure they were consistent with her initial findings, the statement added.
Investigators have begun a file-by-file review of cases handled by Dookhan that is expected to take months. During her nine-year tenure at the lab, she handled more than 60,000 drug samples tied to 34,000 cases.
Dookhan was removed from the testing lab in June 2011 and resigned in March. (Editing by Scott Malone, desking by G Crosse)