Annie Dookhan

In a Wednesday, Oct. 10, 2012 file photo, Annie Dookhan, center, is leaves a Boston courthouse escorted by court officers and her lawyer. (AP Photo/Josh Reynolds, File)

(The Associated Press)

Annie Dookhan, the former state drug lab chemist who faked test results in criminal drug cases, has been paroled from prison.

Her attorney, Nicolas Gordon, told the Boston Herald that Dookhan was released from a women's prison in Framingham about a month ago. She served approximately two years and four months of her three- to five-year sentence.

Gordon told the Herald he believed her lack of a criminal record was a factor in her early release. He did not tell the newspaper whether she was released earlier than the three-year minimum due to good behavior or other factors.

Dookhan pleaded guilty in November 2013 to several counts of obstruction of justice, perjury and tampering with evidence. In addition to her prison sentence, she was ordered to serve two years probation after her release.

State Police said she faked results and tampered with evidence in more than 1,000 criminal cases. She tested more than 60,000 drug samples involving 34,000 defendants during the nine years she worked at Hinton State Laboratory Institute in Boston, police said.

Dozens of inmates were released when questions were raised in 2012 about the validity of the drug test results used in their trials.

Gordon told the Herald that Dookhan is focusing on her family and has not made any decisions about what to do next. Since she previously lied about having a master's degree, one of the conditions of her sentence is that she not use false credentials in seeking future employment.