Lawyers for Colorado theater shooting defendant Holmes seek to bar testimony of bomb experts

FILE -This June 4, 2013 file photo shows Aurora theater shooting suspect James Holmes in court in Centennial, Colo. Holmes is returning to court Monday Oct. 21, 2013 for another round of legal skirmishes over what evidence can be used against him when he goes on trial for the Colorado theater shootings. (AP Photo/The Denver Post, Andy Cross, Pool, File) (The Associated Press)

The battle over what evidence can be used against Colorado theater shooting defendant James Holmes is turning to the testimony of bomb technicians and explosives experts.

Hearings resume Tuesday.

Holmes pleaded not guilty by reason of insanity to charges of killing 12 people and injuring 70 in 2012. At pretrial hearings this month, prosecutors and defense lawyers are trying to persuade the judge to allow or throw out statements Holmes made to police and other evidence. Most of the evidence could be used to bolster or weaken the insanity claim.

Holmes faces murder and attempted-murder charges. His lawyers acknowledge he was the shooter, but they say he was in the grip of a psychotic episode.

Prosecutors are seeking the death penalty, but they must convince jurors that he was sane.