INDIANA — A Western Pennsylvania man has been convicted of first-degree murder for killing his girlfriend's toddler and now faces the death penalty or life in prison.

Twenty-year-old Joshua Louis Turner, of Black Lick, was convicted Thursday in Indiana County in the beating death of 19-month-old Leonard McIntire. The boy died of head trauma a few days after he was beaten at home in October 2008.

Police say Turner initially told them the child fell. But Trooper Timothy Lipniskis testified Turner "started to freak out" after the child bit and hit him.

Turner's attorneys have argued the death penalty is illegal in this case because Turner has a low IQ and the U.S. Supreme Court has outlawed executing mentally disabled people.