Question for Don Vito...
What happens if a defendent does the "silent treatment" through the entire legal process? Basically says nothing, gives no motive, gives no answers, not even as much as a nod?
I've never run into such a thing. It seems to me that for the most part the judge would have fairly broad leeway in dealing with it, like any other sort of disruptive behavior by a defendant.
If he won't even talk to his defense attorney, the attorney would have to file a motion to have him psychologically evaluated to determine whether he is competent to assist in his own defense. I have had to do this twice (not because my client wouldn't talk to me but because he or she seemed crazy or too depressed to make rational decisions), and in both instances my client was found incompetent.
In terms of routine day-to-day interaction with the court, the defendant can be found in contempt if he refuses to participate in the process by not answering questions about routine matters, such as whether he wishes to be represented by the public defender, and essentially held until he agrees to cooperate.
Obviously he can't be compelled to actually testify at trial, and in fact I would not expect he will, unless (like the guy in Norway) he has some wacky agenda he wants to air publicly.