CENTENNIAL — They are a plumber and a teacher, a lawyer and a gas station attendant, a military veteran and an active-duty service member.

The 19 women and five men picked Tuesday in Arapahoe County District Court to decide what constitutes justice in the Aurora movie theater shooting share little more in common than a home county and a commitment to weighing the case impartially. But, for the next four to five months, they will sit beside one another, listening to evidence and ultimately deciding whether James Holmes is guilty for an attack that left 12 people dead and 70 others wounded. And, if they find he is, they will decide whether he should be executed.

What began three months ago with 9,000 juror summonses — among the largest jury calls in U.S. history — reached its end Tuesday evening with a panel of 12 jurors and 12 alternates, mostly white. Only the judge and attorneys know which jurors are alternates until it comes time for deliberation.

Opening statements in the trial are scheduled for shortly after noon April 27.

At the start of jury selection’s final day Tuesday, Arapahoe County District Attorney George Brauchler cautioned the remaining jurors that the case will be “a roller coaster through the worst haunted house you can imagine.” Defense attorney Tamara Brady suggested the task for the jurors will strain the very limits of the jury system.

“I’m going to start by telling you how nervous I am and how nervous my colleagues are about whether Mr. Holmes can get a fair trial in this case or about whether it’s just too big,” she said.

In their final questioning of jurors Tuesday, both sides offered what was perhaps a preview of those key statements. Brauchler asked jurors whether they would be OK never learning conclusively about why the shooting occurred. Although prosecutors will present evidence of motive, he said, it may remain an “itch that isn’t scratched,” he said.

Brady used many of her questions to tear at perceptions of Holmes.

Several times, defense attorneys accused the prosecution of dismissing Latino jurors based on ethnicity, challenges that the judge denied.

When the process finished, well after the rest of the courthouse had closed, Judge Carlos Samour Jr. was brief in marking the milestone moment.

“OK, folks,” he said. “This is our jury.”

Jurors at a glance

Seat 1: Juror No. 640. Woman. Works as a plumber. Said she has been diagnosed with ADHD. “I know what it’s like to be a little bit different from other people,” she said during individual questioning.

Seat 2: No. 17. Woman. Lawyer and business owner. Of the death penalty, she said: “I think it has to be the exception to the rule, rather than the rule.”

Seat 3: No. 329. Woman.

Seat 4: No. 661. Woman. Teaches classes on dental assisting. Daughter attended premiere of the Batman movie on the same night as the shooting but at a different theater. Defense tried to get her removed from the pool after individual questioning.

Seat 5: No. 535. Woman. “I don’t think I’d have a problem at all with guilty, not guilty, not guilty by reason of insanity,” she said during group questioning.

Seat 6: No. 87. Woman. On her juror questionnaire, she wrote, “I used to believe in eye-for-an-eye, but now, knowing more about mental illness, I would have to consider everything involved.”

Seat 7: No. 901. Woman.

Seat 8: No. 495. Woman. Teared up during individual questioning when asked whether she could deliver a death sentence.

Seat 9: No. 872. Woman. Was asked during group questioning whether she would infer anything about James Holmes’ mental state from his hair style in court. “It’s probably just a haircut,” she said.

Seat 10: No. 1,009. Woman. Said during group questioning that she didn’t have many concerns about serving on the jury. “My main concern was just my privacy,” she said.

Seat 11: No. 118. Woman. Said her son-in-law is a corrections officer and an Iraq war veteran who suffers from post-traumatic stress disorder. “I think mental illness is a fact of life,” she said. “A lot of us have been touched by it.”

Seat 12: No. 983. Man.

Seat 13: No. 378. Woman. Expressed reservations about how the outcome of the case will be perceived by the public. “Of course, it’s going to be in the back of my mind,” she said. “But it’s going to have to stay in the back.”

Seat 14: No. 155. Man. Was living in California at the time of the shooting. He didn’t know how many people were killed and wounded in the shooting until he came to court.

Seat 15: No. 527. Man.

Seat 16: No. 673. Woman who serves in the military. Has three kids, and her husband is deployed. Asked whether she wanted to serve on the jury, she said, “I don’t want to be part of it, to be honest.”

Seat 17: No. 737. Man. “I’m the world’s worst liar,” he said during group questioning.

Seat 18: No. 706. Woman. Retired after a 22-year career in the Army as an intensive care nurse. Asked whether she could handle weighing the numerous charges in the case, she replied, “How do you eat an elephant? One bite at a time.”

Seat 19: No. 412. Woman. Works in the information technology department at the Aurora Mental Health Center. Previously served as a law enforcement agent in the Air Force and called herself “very strongly in the middle.”

Seat 20: No. 267. Woman. Works as an attendance clerk at a school. Two students from her school were at the Aurora theater that night, she said.

Seat 21: No. 557. Woman. Said she found the prospect of serving on the jury scary. “But it’s part of our responsibility and our legal system,” she said.

Seat 22: No. 307. Woman. Works as a teacher of special-education children. Said she used to be more liberal and against the death penalty but has become more open to it. “Just growing up,” she said.

Seat 23: No. 311. Woman. Said she needed to hear all the evidence in the case before she could make a decision. “I don’t think you actually know what you’d really do until you hear everything.”

Seat 24: No. 313. Man. Works at a gas station. His employer won’t pay him while he’s serving, but he said he could scrape by on $50 a day.