FORT HOOD, Texas (AP) —An Army psychiatrist will not be allowed to tell jurors that he gunned down Fort Hood soldiers to protect the lives of Taliban leaders in Afghanistan, a military judge ruled Friday.

Maj. Nidal Hasan’s “defense of others” strategy fails as a matter of law, Col. Tara Osborn said during a 45-minute hearing. That defense strategy means that a killing was necessary to prevent the immediate harm or death of others.

Osborn said no soldiers at the Texas Army post on Nov. 5, 2009, posed an immediate threat to anyone in Afghanistan. She said the legitimacy of the Afghanistan war is not an issue at Hasan’s trial, which has not started. She also ordered Hasan not present any evidence or arguments about his claims that deploying U.S. troops posed an immediate threat to Taliban fighters.

Hasan, an American-born Muslim, faces the death penalty or life without parole if convicted in the rampage that left 13 dead and nearly three dozen wounded.

Not everyone killed was about to deploy to Afghanistan or elsewhere. Pvt. Francheska Velez, who was pregnant, had just returned from Iraq. Michael Grant Cahill, who tried to stop the gunman with a chair, was a physician assistant who worked in the buildling.

Hasan asked for a three-month trial delay to prepare for his defense after Osborn last week granted his request to serve as his own attorney. But that delay seems unlikely since Osborn rejected his defense strategy; she has not ruled on his request.

Osborn said last week that Hasan would represent himself unless he changed his mind or disobeyed the court’s orders and trial rules.

Hasan’s former defense attorneys have been ordered to assist him if he asks. The next hearing is on Tuesday, and Osborn is to address the defense attorneys’ new motions on what they view as their role as standby attorneys.

Earlier this week, the lawyers said complying with the judge’s order would require them to act unethically. They say it’s not their role to give Hasan legal advice, and indicated they may withdraw from the case. That may change due to Osborn’s decision Friday.

Jury selection was set to begin two weeks ago, and then was tentatively moved to last week. It’s been on hold as various matters remain unresolved.

Witnesses have said that after lunch on Nov. 5, 2009, a gunman wearing an Army combat uniform shouted “Allahu Akbar!” — “God is great!” in Arabic — and opened fire in a crowded medical building where deploying soldiers get vaccines and tests. Witnesses said the gunman fired rapidly, pausing only to reload, even shooting at some soldiers as they hid under desks and fled the building.

Government documents show that in the years before the shooting, Hasan told some colleagues that the U.S. was at war with Islam. In some emails to a radical Muslim cleric, Hasan indicated that he supported terrorists and was intrigued with the idea of U.S. soldiers killing comrades in the name of Islam.

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