Police Sgt. Gerald Jonsgaard said Holmes stopped the theater door from locking by using a small piece of plastic commonly used to hold tablecloths onto a picnic table. Jonsgaard also said he spotted a shotgun and a large drum magazine that appeared to be jammed on the floor of the theater.

Holmes' attorneys are expected to argue that their client has "diminished capacity," a term that, according to the Colorado Bar Association, relates to a person's ability or inability "to make adequately considered decisions" regarding his or her legal representation because of "mental impairment or for some other reason."

Several times, on cross-examination, they have asked witnesses about Holmes' demeanor and what he looked like when police found him.

The day's testimony concluded with a detective who interviewed people wounded in the attack and the two coroners who conducted the 12 autopsies.

After the hearing, Arapahoe County District Judge William Sylvester will determine whether there is enough evidence for Holmes to stand trial.

Security was tight at the hearing. Spectators had to pass through a metal detector and then were searched again before entering the courtroom. At least nine armed officers stood guard inside, some of them scanning the audience packed with reporters and victims' family members.

Holmes did not speak during the hearing. His bushy hair and long beard contrasted with the bright red hair and close-cropped looks he sported during previous appearances.

During portions of the hearing, family members of victims held one another, sobbing.

Earlier in Monday's hearing, police Officer Jason Oviatt -- the first officer to encounter Holmes after the rampage ended -- testified that Holmes seemed "very, very relaxed."

Holmes, his pupils dilated, sweating and smelly, didn't struggle or even tense his muscles as he was dragged away to be searched.

"He seemed very detached from it all," Oviatt testified, describing Holmes as unnaturally calm amid the chaos and carnage.

Oviatt testified Monday that within minutes of the first calls, he responded to the theater and found Holmes standing outside in a helmet and gas mask, his hands atop a white coupe that turned out to belong to him.

At first, Oviatt said, he thought Holmes was a police officer, but as he drew within 20 feet, he realized something was terribly wrong.

"He was just standing there. All the other officers were running around, trying to get into the theater," Oviatt said.

A trail of blood led from the theater. The rifle that authorities believe Holmes used in the attack lay on the ground near the building.

Holmes calmly complied with all Oviatt's orders, the officer testified.

Another officer, Aaron Blue, testified later that Holmes matter-of-factly told him, without prompting, about the complex web of explosives that authorities would later find in his Aurora apartment.

He told Blue that the devices "wouldn't go off unless we set them off."

Holmes was a doctoral student in the neuroscience program at the Anschutz Medical Campus of the University of Colorado, Denver, in Aurora, until he withdrew a month before being arrested outside the bullet-riddled movie theater. He had been a patient of a University of Colorado psychiatrist, according to a court document filed by his lawyers.

His only brush with the law in Colorado appears to have been a 2011 summons for speeding from Aurora police.