let's bring in our senior legal analyst jeffrey toobin. you know, what jumped out at me, jeff, is that the m.i.t. police officer sean collier was killed after apparently these allegations if they're true the three students recognized the picture and apparently failed to call the fbi or local police and say we know who at least one of the suspects is. i wonder if they potentially could be charged with some sort of involvement in negligent homicide if you will in the death of that m.i.t. police officer? >> i think that's unlikely. it's very difficult to prosecute people for failing to act. that's been a traditional dilemma in american law about how you can hold people responsible for moral faults like that, but that is no really a criminal offense. they're in a world of trouble for what they did do. i think it's going to be difficult to prosecute them for what they didn't do. >> if they would have immediately called the campus police or the local police or