Due to widespread criminal misconduct of a lab's chemist in analyzing drug samples, Massachusetts has decided to dismiss approximately 20,000 drug convictions.

ACLU staff attorney Carl Williams responded, "This is a victory for regular people, for people who've een tarnished by these drug convictions."

Those drug convictions relied on the analysis from Annie Dookhan, a former chemist for the Department of Public Health, worked on testing drug samples from 2003 to 2012.  Investigators accused her of contaminating drug samples, falsifying results, and mishandling evidence. 

Dookhan pleaded guilty in November of 2013 to intentionally contaminating some samples to turn them from negatives samples into positive samples and to "dry labbing" in which she tested a few samples but reported the same results for multiple other samples.  Dookhan was sentenced to 3 to 5 years in prison and was released last year.

The Supreme Judicial Court of Massachusetts ruled in January that going through each case was too time consuming and ordered district attorneys to produce a list by Tuesday of drug convictions that they planned to dismiss.

Prosecutors identified 15,570 drug convictions to be dismissed in Suffolk County alone.  

"If there had been evidence that any of these defendants was actually innocent, we would not have hesitated to dismiss the case outright and exonerate the defendant immediately," said district attorney Dan Conley.

None of the defendants whose convictions were vacated had been imprisoned solely on Dookhan-related cases.