The stakes in the penalty phase create an unusual dynamic in what was already a very unusual case.
"The U.S. military is not used to this kind of defendant, who apparently wants to die for his crimes. It might take a terrible weight off the jury -- if the inmate wants death, they may say, 'we'll accommodate.' It lessens the burden," said Richard Dieter of the Death Penalty Information Center. "On the other hand, the military by its nature, and in this time of war, sees a lot of death. They may not desire to add to it and give (Hasan) what he may want. His wishes might have a reverse effect."
But Hasan's confessed rampage against innocents on a domestic military base will be an important consideration for the panel considering his fate.
History may not be on Hasan's or the government's side. The last military execution was in 1961, and only five servicemen sit on death row at Fort Leavenworth, Kansas.
The military has its own legal standards and procedures when trying and appealing capital cases. The U.S. Supreme Court gets the final say, if any petition reaches that far. Of the 11 military death sentences that have completed direct appeal, nine (82%) have been reversed.