Why not treat it as criminal? Massachusetts law allows for life without parole for multiple murder, combined with aggravated assault and arson. Simple as that. There seems to be ample evidence to press those charges.

The death penalty (aka offering the little twerp a chance at early martyrdom) would not be desirable. Nor would terrorism charges, really, since they would allow for discussion of his political motives at trial, giving him a pulpit from which to speak.

Nope. Treat him as a common killer, and the only question becomes: did you set off those bombs and shoot down the MIT cop? Yes? Enjoy your stay at Walpole, hope your roomie thinks you're cute.

MAYBE offer him a plea bargain and possibility of release after 20 years IF he comes out with verifiable evidence about the people who put them up to this.