Nearly 23,000 people may have their convictions overturned over a drug-lab scandal in Massachusetts, following a five-year court battle over a chemist who worked on a large number of cases. Middlesex County District Attorney Marian Ryan has said that prosecutors are still working through whose cases will be dismissed or vacated. "It's absolutely stunning. I have never seen anything like it," said professor Suzanne Bell. "It's unbelievable to me that it could have even happened. And then when you look at the scope of the number of cases... there are no words for it." Ryan will announce the names by April 18, her office said. The state ruled in January that the DA's office can only choose to retry a small subset of cases.