A military jury has sentenced Army Maj. Nidal Hasan to death for killing 13 people during a 2009 shooting rampage at Fort Hood.
Hasan previously said the attack on unarmed soldiers was motivated by religion.
The former Army psychiatrist said he has a desire to protect Muslim insurgents fighting in Iraq and Afghanistan.
If the death sentence is carried out, Hasan would become the first American soldier executed in more than half a century.
The military justice system requires a lengthy appeals process which means it could be years before he is put to death.