of boston, bombing suspect dzhokhar tsarnaev is living in solitude, in a 10x10 cell equipped with a steel door, and ama window where he s being observed 24 hours a day. the accommodations are bare, limited to a toilet, sink and bed. in a restricted area reserved only for high risk inmates. there s only room for 30 offenders in this special section and now tsarnaev is one of them. as investigators try to figure out how and why he allegedly carried out the attacks with his brother, later killed in a police shoot-out, the justice department s role in the investigation has come under intense scrutiny. tsarnaev has stopped giving substantive information to authorities since being read his miranda rights, sources have indicated. in an exclusive interview with cnn s brianna keilar at the white house correspondents dinner saturday night, attorney general eric holder defended the decision. will you comment on the suspect being mirandized and whether that was appropriate? well, i mean, the d