James Holmes Update: Suspect plans change to insanity plea in Colo. movie theater shooting

(CBS/AP) DENVER - Lawyers for James Holmes, the man accused of killing 12 people and injuring 70 in a Colorado movie theater last July, said Tuesday Homes wants to change his plea to not guilty by reason of insanity.

PICTURES: The Colorado massacre suspect

Attorneys for Holmes said in a court filing they plan to formally ask for the change of plea at a May 13 hearing.

A judge in the case previously entered a standard not guilty plea for Holmes. If the judge accepts the insanity plea, Holmes would be sent to the state mental hospital, where doctors would determine whether he was insane at the time of the July 20, 2012 shootings.

If the doctors do determine that Holmes was insane, a jury could still find him guilty.

The insanity plea was widely expected given the compelling evidence against Holmes. He is charged with multiple counts of murder and attempted murder. Prosecutors are seeking the death penalty.

Holmes' attorneys have said in court hearings and written in court documents that Holmes is mentally ill. He was being seen by a psychiatrist before the attack at a midnight screening of the latest Batman movie, "The Dark Knight Rises."

Prosecutors say Holmes spent months buying guns and thousands of rounds of ammunition, donned police-style body armor and opened fire in a crowded Aurora theater.

Holmes could be executed if he's convicted of more than 160 counts of murder and attempted murder.

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