James Eagan Holmes
James Eagan Holmes' change in plea from "not guilty" to "not guilty by reason of insanity" has been accepted by a Colorado judge. Reuters

Lawyers for accused Aurora theater mass shooter James Holmes are seeking access to tapes of their client when he was in psychiatric care in Denver as they prepare to mount an insanity defense.

The tape is expected to provide details of Holmes’ mental state while he was committed at Denver Health Medical Center shortly after being charged with the July 2012 slaughter that killed 12 people and wounded 70 others at the Century 16 movie theater in Aurora, Colo. Attorneys for Holmes said the Arapahoe County Sheriff’s Department has rebuffed requests for the tapes, and the lawyers filed a motion demanding a copy of the video.

Holmes is scheduled to undergo a mental health evaluation Aug. 2 at the Colorado Mental Health Institute in Pueblo, according to KKTV. In the motion, Holmes’ attorneys said the doctor expected to conduct the evaluation believes the tape will be helpful in carrying out his court-ordered duties.

Should the evaluator determine that Holmes is insane, the findings will only be introduced as evidence and the jury would still have to decide if Holmes was unable to determine right from wrong during the shooting. By mounting an insanity defense, Holmes’ attorneys are already conceding that he committed the shootings.

"He [the psychiatrist] expressly stated that video footage of Mr. Holmes while he was hospitalized at Denver Health is relevant to his sanity examination, and that he would like to view this footage," the motion stated, according to the Denver Post.

The motion was filed Tuesday, the same day an Arapahoe County judge estimated that as many as 3,500 prospective jurors will be summoned as jury selection gets under way in the case, the Associated Press reported.

Holmes’ trial is scheduled for Feb. 3, but the AP said the jury selection process is expected to be arduous. The news wire service pointed out that 40,000 pages of evidence have been produced for the case so far and Holmes’ attorneys have filed 130 motions.

There are still more motions to come, as the defense signaled it plans to seek a change of venue for the trial, due to the enormous publicity generated by the case.

The July 20 mass shooting was carried out during the midnight premiere of the Batman film “The Dark Knight Rises.”

Holmes faces the death penalty if convicted of the charges against him, which include 166 counts of murder and attempted murder.