 constituted in a violation of criminal law. As a result, I concur with CMPD's decision not to seek criminal charges against him. End quote. Brett Jensen, WBT News. Mistrial in Massachusetts. Karen Reid on trial for killing her police officer boyfriend. Jury cannot reach a unanimous decision. Your service is complete. I'm declaring a mistrial in this case. Judge Beverly Canone, Reid is accused of murdering Boston cop John O'Keefe, running over him with her car and leaving him to die in a snowbank.