Accused Fort Hood gunman Major Nidal Hasan is expected to tell a military judge on Tuesday how he plans to argue he was protecting the Taliban when he opened fire on dozens of people at the facility in 2009.
The Army psychiatrist could face the death penalty if convicted of premeditated murder on charges he killed 13 people and wounded 32 in the worst shooting rampage on a U.S. military post.
Hasan, 42, told the presiding judge in the case, Colonel Tara Osborn, last week that he was defending the Islamic Emirate of Afghanistan, the Taliban and its leader Mullah Omar when he fired on soldiers in a readiness facility, many of whom were getting ready to deploy to Iraq.
At the time of the shooting, Fort Hood was a major deployment point for the conflicts in Iraq and Afghanistan.
Hasan had been preparing to leave for Afghanistan with a unit assigned to help soldiers deal with mental issues when authorities said he opened fire on a medical station where soldiers go for exams and vaccines.
The accused shooter has not explained how his actions might be construed as protection of the Taliban.
Osborn may issue a ruling on whether Hasan, who will represent himself at his court-martial, can use the "defense of others" argument. She also could rule on his request for a three-month delay in the trial, now set to begin on July 1.
A Fort Hood spokesman said it was "entirely up to the judge" whether she will issue rulings or simply hear testimony on Tuesday.
The hearing was rescheduled from last week, when Osborn said both sides were late getting court filings to her and it was "obvious" they needed more time to prepare.
She released the prospective jurors until further notice, delaying jury selection until after the hearing.
Sergeant Alonzo Lunsford, who was shot five times during the attack and lost sight in his right eye, expressed frustration at the repeated delays in the case.
"Throughout this whole process, he's been treated like he is the victim, and we have been treated as if we really don't matter," Lunsford told Reuters.
Richard Rosen, a former prosecutor at Fort Hood and currently a law professor at Texas Tech University, said he expects Osborn will reject Hasan's "defense of others" argument.
"Hasan's claim is like an American soldier shooting fellow GIs during World War Two, and then asserting that he was only trying to protect the Nazi leadership," Rosen said.
"Defense of others is flatly inapplicable," he said. "There was no immediate threat to any others from the victims of Hasan's attack."
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