A forensic psychologist says the ex-Marine who shot "American Sniper" author Chris Kyle and another man wasn't legally insane, but had a paranoid disorder made worse by using alcohol and marijuana.

Prosecutors on Friday called a rebuttal witness in the trial of Eddie Ray Routh, who's charged with killing Kyle and his friend Chad Littlefield. Routh's attorneys, who are pursuing an insanity defense, rested their case Thursday.

Routh is charged with killing the two men in 2013 at a gun range.

Dr. Randall Price testified that he thought Routh "did know what he was doing was wrong, and he did it anyway."

The 27-year-old Routh faces life in prison without parole if convicted.

The Oscar-nominated film based on Kyle's memoir has spurred intense interest in the case.

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