More defendants are expected to challenge their convictions this week based on a testing scandal at a Massachusetts drug lab, including a man currently under indictment for murder and another man who served time behind bars for killing a neighborhood cat and burning its remains.

A Suffolk Superior Court judge is hearing requests for sentences to be put on hold and bail set for defendants currently serving prison sentences in cases in which chemist Annie Dookhan tested suspected drugs.

Dookhan is accused of skirting protocols and faking drug test results at a now-closed state lab.

Anthony Thames is charged with murder for allegedly shooting a man in Boston in 2011. Shortly after his arrest, he pleaded guilty to drug charges and is currently serving a five-year sentence. (AP)