New questions rise in shutdown of drug lab

BOSTON (WHDH) -- There are new questions about the shutdown of a drug lab where a chemist is accused of failing to follow testing protocol.

7News obtained documents showing the state began investigating the lab more than six months ago.

Those documents reveal the problems were first noticed in June of 2011.

Governor Deval Patrick shut down the lab last week.

Those violations could force the re-trial of thousands of people convicted on drug charges.