A US judge entered a plea of not guilty on behalf of alleged Aurora theater gunman James Holmes on Tuesday, after his lawyers said they were not ready to enter a plea.
The judge left it open for lawyers for the 25-year-old to enter a plea of not guilty by reason of insanity at a later date, at Holmes's arraignment for the killing of 12 people in the Colorado town of Aurora last July.
Judge William Sylvester set a trial date for August 5 for Holmes, who watched proceedings wearing a reddish prison jump suit in a courtroom packed with relatives and media.
When Holmes first appeared in court last year he had bright orange hair and looked befuddled. He has since let his hair color grow out, and on Tuesday sported curly brown hair and a beard.
The judge set a schedule of pre-trial hearings, including one on April 1 at which prosecutors can file a motion as to whether they will seek the death penalty for Holmes.
There will be three days of pre-trial hearings from May 13-15, and another hearing on July 25, before the full scheduled trial.
Defense attorney Daniel King said he would be ready to make a plea by May 1 or June 1. Prosecutors objected and said they had waited long enough, to which the judge agreed and entered a standard not guilty plea.
Holmes is accused over the July 20 massacre at a midnight screening of the Batman movie, "The Dark Knight Rises," which revived America's long-running debate about gun control.
Witnesses said Holmes threw smoke bomb-type devices before opening fire randomly with weapons, including an AR-15 military-style rifle, a 12-gauge shotgun and a .40-caliber pistol.
Holmes' arraignment had initially been scheduled for January, but the judge agreed at that time to delay it, triggering anger from some of the victims' relatives.
During three days of pre-trial hearings in January, prosecutors called witnesses who gave chilling accounts of the slaughter, and played 911 emergency calls in which the chaos and loud booms of gunshots could be clearly heard.
They presented evidence that Holmes had planned the attack well in advance.
It included photos found on his iPhone suggesting he had surveyed the cinema weeks before the shootings. There were also several images showing him posing with guns and explosive devices hours before the massacre.
Holmes made at least 16 purchases from May to July 2012, including four firearms, incendiary devices and almost 6,300 rounds of ammunition, the court heard.
The father of one victim yelled "rot in hell!" at Holmes when the judge delayed officially charging him in January.
Steve Hernandez, father of victim Rebecca Wingo, was escorted out by courtroom guards after his outburst, and only allowed back in after apologizing and promising the judge he would behave himself in future.