From the Boston Globe:
Dzhokhar Tsarnaev admitted to authorities Sunday that he and his brother were behind the Marathon bombings, according to a senior law enforcement official.
Tsarnaev made his admissions to FBI agents who interviewed him at Beth Israel Deaconess Medical Center, where he is being treated for multiple gunshot wounds. He had not yet been given a Miranda warning.
Tsarnaev’s attorneys are certain to challenge the legal admissibility of those admissions, and other information he gave them, such as claiming that he and his brothers acted alone, and that his brother was radicalized in an extreme form of Islam in part because he opposed US actions in Iraq and Afghanistan.
Is this confession admissible, since there were no Miranda warnings?
The state will argue the national security exception excuses the use of the warnings. The defense will argue that the exception does not apply since there was no evidence that the defendant would be involved or knew about any future acts of terrorism. They will also argue (or at least I would) that a confession in a hospital bed by a defendant recovering from serious injury was inherently coercive and independent of the Miranda issue the confession should still be excluded.
The article says that the Prosecution doesn't need the confession since they have the testimony of the kidnapped victim and other evidence.
I have to say, though, as an ex-prosecutor I would have given him the warnings. I had one case where a man murdered his wife and two year old child - and still confessed after we warned him. I don't think giving him the Miranda warnings would have mattered here - my guess he is going to talk anyway.