The Virginia Supreme Court has upheld the death sentence of John Muhammad, the elder of pair convicted in the 2003 "sniper" attacks. There were two good arguments in the case, but the Court ruled against both:

The court brushed aside arguments that Muhammad could not be sentenced to death under state law because he was not the triggerman. And it rejected claims that the post-Sept. 11 terrorism law under which he was prosecuted is unconstitutionally vague.

It was close on the triggerman argument though:

The Supreme Court unanimously affirmed the conviction based on the terrorism law but split 4-3 in upholding the conviction under the triggerman rule. The court's majority found that even if Muhammad's teenage accomplice, Lee Boyd Malvo, pulled the trigger, Muhammad was eligible for the death penalty as an "immediate perpetrator" of slaying.

Background on the triggerman argument is here, and the previously untested terrorism law here.