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

James Holmes, 24, is in custody after allegedly going on a shooting rampage during a midnight showing of "The Dark Knight Rises" at a Century 16 movie theater in Aurora, Colo., on July 20, 2012. Aurora Police said witnesses reported the shooter was wearing a gas mask and released some type of a canister in the dark theater just after the movie began. Officers found the suspect near a car behind the theater and also located a gas mask, rifle, handgun and at least another weapon. This file photo provided by the Arapahoe County Sheriff's Office shows James Holmes, who faces multiple counts of first-degree murder and attempted murder.
AP Photo/Arapahoe County Sheriff
James Holmes faces multiple counts of first-degree murder and attempted murder in the July 20, 2012 theater shooting in Aurora, Colo.
AP Photo/Arapahoe County Sheriff

(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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