( CNN ) -- A judge has ordered that accused Colorado movie theater shooter James Holmes undergo an additional sanity examination , saying there was good cause to believe previous testing was `` incomplete and inadequate , '' according to a ruling issued Wednesday . Arapahoe County District Judge Carlos Samour Jr. ordered Holmes to undergo an independent exam by the Colorado Mental Health Institute in Pueblo by early March , and the report must be filed by July 14 . Samour further ruled the new examiner may not take into account any mitigating factors that are identified in the state 's death penalty statutes . Prosecutors are seeking the death penalty against Holmes , who is accused of opening fire in a packed movie theater in Aurora , Colorado , during a July 2012 midnight showing of the latest Batman installment , `` The Dark Knight Rises . '' Authorities have said Holmes was dressed head to toe in protective gear . Holmes allegedly threw tear-gas canisters in the theater and then opened fire on the patrons , according to witnesses . Police say he used several weapons , including an AR-15 rifle , before fleeing the theater . Outside the theater , the shooter was apprehended , identifying himself to police as `` The Joker , '' one of Batman 's archenemies . Holmes faces 166 charges in the rampage that left 12 people dead and dozens more wounded . Holmes was a neuroscience doctoral student at the University of Colorado 's Anschutz Medical Campus until the month before the attack ; prosecutors have argued that he began plotting his attack while still enrolled . The defense , meanwhile , appears to be focused not so much on what Holmes allegedly did that night but his mental state then and earlier . A psychiatrist who treated him had warned campus police at the University of Colorado how dangerous he was , prompting them to deactivate his college ID to prevent him from passing through any locked doors , according to court documents .
District Judge Carlos Samour Jr. ruled James Holmes must undergo a new exam . Defense attorneys claim Holmes is not guilty by reason of insanity . Holmes is charged with opening fire in movie theater , killing 12 people .