The Army psychiatrist accused of killing 13 people and wounding dozens more in the Fort Hood shooting four years ago told jurors in opening arguments Tuesday evidence will "clearly" show that "I am the shooter."
But Maj. Nidal Hasan insisted there's more to the story.
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Acting as his own attorney, Hasan told the court in Texas he plans to call two defense witnesses and also cited his religion as a possible defense but did not elaborate.
He said the evidence will show "that we are imperfect Muslims trying to establish the perfect religion... I apologize for any mistakes I made in this endeavor."
Hasan is charged with 13 counts of premeditated murder and 32 counts of attempted murder in the 2009 attack -- the deadliest mass shooting ever on a US military base.
Prosecutors say Hasan targeted "those wearing the uniform" during his rampage because he did not want to be deployed.
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They claim he methodically prepared for the attack by practicing at a local shooting range, making frequent visits to a gun store to stock up on ammunition and studying the schedule of the building he carried out the shooting in.
Hasan also plans to cross-examine victims of the rampage himself.
“I will be cross-examined by the man who shot me,” Staff Sgt. Alonzo M. Lunsford Jr., 46, who retired from the Army and remains blind in his left eye from the shooting, told The New York Times. “You can imagine all the emotions that are going to be coming up.”
Hasan could receive the death penalty if convicted.