About 23,000 people are expected to have low-level drug convictions wiped away next month, the culmination of an epic drug-lab scandal in Massachusetts, NBC News reported.

It comes five years after a rogue chemist admitted to tampering with evidence, forging test results and lying about it, resulting in 24,000 people with questionable convictions. Prosecutors fought to preserve the convictions, but a court ordered them to decide who they can realistically try to re-prosecute.

They are still working through the list, but their answer is expected to be "in the hundreds," a spokeswoman for one district attorney said this week.

"It's absolutely stunning. I have never seen anything like it," said Suzanne Bell, a professor at West Virginia University who serves on the National Commission of Forensic Science. "It's unbelievable to me that it could have even happened. And then when you look at the scope of the number of cases that may be dismissed or vacated, there are no words for it."

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