A chemist who tested more than 60,000 drug samples submitted in the cases of about 34,000 defendants over nine years has admitted to faking drug sample results, according to a police report obtained by the Associated Press.

The revelations about the chemist, Annie Dookhan, who is also accused of having fabricated a master's degree in chemistry from the University of Massachusetts, throws thousands of criminal cases into question because of tampered evidence and the fact that she 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 AP. "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, 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 Boston Globe reports that the office of Massachusetts Governor Deval Patrick has identified 1,141 inmates in Massachusetts jails and prisons convicted based on evidence handled by Dookhan, who was also the quality control officer in the lab.

"I intentionally turned a negative sample into a positive a few times," Dookhan said in a signed statement she gave police.

She also admitted to identifying drug samples by looking at them instead of testing them, contaminating samples to get more work finished and saying drug evidence was heavier than it actually was, according to the AP.



Authorities have not filed criminal charges against Dookhan or commented on her possible motives.