Treason? We're not talking Benedict Arnold here.
From the Uniform Code of Military Justice.
918. ARTICLE 118. MURDER
10. Punitive Articles
Any person subject to this chapter whom without justification or excuse, unlawfully kills a human being, when he- –
(1) has a premeditated design to kill;
(2) intends to kill or inflict great bodily harm;
(3) is engaged in an act which is inherently dangerous to others and evinces a wanton disregard of human life; or
(4) is engaged in the perpetration or attempted perpetration of burglary, sodomy, rape, robbery, or aggravated arson;
is guilty of murder, and shall suffer such punishment as a court-martial may direct, except that if found guilty under clause (1) or (4), he shall suffer death or imprisonment for life as a court-martial may direct.