Roundup: Colorado shooter trial begins

The trial of James Holmes officially began Tuesday as the first group of prospective jurors were questioned in court to decide their eligibility to judge the man accused of one of the worst mass killings in U.S history.

A jury pool of 9,000 people, the largest in U.S. history, will be narrowed down to a 12-member panel and 12 alternatives who will decide his fate in a process that is expected to take several months before any evidence is heard.

Holmes faces 166 counts of murder and attempted murder as 12 people were killed and 70 wounded after he opened fire on July 20, 2012 with automatic weapons into a packed movie house watching the midnight premiere showing of Batman' s The Dark Knight Rises.

Holmes has pleaded "not guilty by reason of insanity," but prosecutors will try to show he preplanned the shooting, was sane at the time, and should be executed.

The defense has said he was in the "throes of a psychotic episode" at the time and should face life imprisonment.

In several groups, the first wave of 250 prospective jurors filed into court Tuesday, and were told by Arapahoe County Judge Carlos A. Samour not to discuss the case with anyone, especially on social media, and not to carry out any independent research.

"The jury must decide this case based only on the evidence presented in the courtroom and the law I will provide," he told the first group of 20, mostly white women, who entered the courtroom.

Samour has defended the large number of people summoned as his way to find an impartial jury for such a high-profile, emotive case. Following the judge' s instructions, each person spent several hours answering 77 questions, not made public, about their views on topics such as the death penalty and insanity defenses.

After Tuesday, groups of 250 will follow the same routine every morning and afternoon for the next month. Individual jury selection, scheduled to begin on February 17, will be affected by how they answer the questionnaire.

Holmes appeared in court wearing glasses for the first time and looking more like a Neuroscience Major studying for a Ph.D. at the University of Colorado, his status at the time of the shooting. He was wearing a blue blazer, khaki pants and a striped, open-collared shirt, not the orange prison garb he has previously worn in court. His hair was brown and neatly trimmed, not unkempt and dyed orange as it was when he was arrested without resistance outside the movie theater two-and a-half years ago.

"Absolutely extraordinary..." said former Denver prosecutor Craig Silverman about the size of the jury pool, that was whittled down to 7,000 due to returned mail and viable excuses, but is still the largest on record.

By comparison, 3,000 prospective jurors were summoned last year for selection in the trial of accused Boston Marathon bomber Dzhokar Tsarnaev, and the celebrated 1994 O. J. Simpson case in 1994 drew 1,000. Endi