Four years ago this November, Major Nidal Malik Hasan opened fire on soldiers at the Fort Hood Army Base in Killeen, Texas, killing 13 people and injuring many more.
Today, Major Hasan's trial begins. He faces 13 counts of premeditated murder and 32 counts of attempted premeditated murder.
The Army has already spent more than $5 million on the case, mainly on security. But there are other reasons why this case is unprecedented.
Geoffrey S. Corn, a former Army prosecutor and defense lawyer and a professor at the South Texas College of Law, explains.
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