interrogation. this suggests this man actually attacked the fbi agent, after he implicated himself in a gruesome triple murder that involved one of the marathon bombers. mark eiglarsh is a former prosecutor, and arthur idela. good to see you both. this involves tamerlan tsarnaev before he bombed the boston marathon, had allegedly committed a triple homicide with allegedly this guy who after the marathon bombing was interrogated by the fbi. what's your link to tamerlan tsarnaev and so on. mark, that interrogation went bad. >> oh it sure did. i'm not here to say with certainty that the officer wasn't justified in shooting this man. the problem is, for sure we know it was a homicide. meaning he was shot at the hand of an fbi agent. whether it's murder or not