Lonnie and Sandy Phillips, parents of Aurora theater shooting victim Jessica Ghawi, hug before entering the courthouse on Tuesday. (Brennan Linsley/AP)

The Colorado jury asked to determine whether to convict the gunman who opened fire inside an Aurora movie theater in 2012 — killing a dozen people and wounding scores more — has spent weeks listening to emotional, fraught testimony, learning about evidence and hearing victims recount the horror they endured.

On Wednesday, more than two months after opening statements began in the trial, the case fully moved into the jury’s hands. Jurors began deliberating on Wednesday morning, court officials said, and it is not clear how long the process will take. They finished their first day of deliberations without reaching a verdict.

James Holmes has pleaded not guilty by reason of insanity. His attorneys acknowledged in a court filing two years ago that he was the gunman, writing that Holmes “was in the throes of a psychotic episode when he committed the acts that resulted in the tragic loss of life and injuries sustained by moviegoers on July 20, 2012.”

During the trial, the defense argued that Holmes’s mental illness was to blame for the shooting. Prosecutors said that Holmes meticulously planned the crime, insisted he was sane and argued he should be held responsible for the bloodshed.

Ashley Moser, who was paralyzed, suffered a miscarriage and lost her 6-year-old daughter in the shooting, testified last week. (Colorado Judicial Department via AP)

“He came there with one thing in his heart and in his mind, and that was mass murder,” District Attorney George Brauchler said Tuesday during his closing argument, according to Reuters. Meanwhile, Daniel King, a lawyer for Holmes, said Holmes “had lost touch with reality. He had been consumed by a psychotic process.”

The verdict here would seem to hinge on this major question: Was Holmes sane at the time of the attacks? Holmes faces 165 total charges in this case, nearly all of them for murder or attempted murder, as well as one count of possessing an explosive device. He can be found guilty, not guilty or not guilty due to insanity for any one or all of the charges; prosecutors in this case had to prove to jurors beyond a reasonable doubt that Holmes was not insane.

Jurors are beginning their deliberations just days before the third anniversary of the massacre, which occurred during a midnight screening of “The Dark Knight Rises.”

Witnesses at the time said that Holmes calmly and silently walked through the theater, shooting at adults and children alike gathered for the movie. During the trial this year, victims and others offered tearful, pained stories of what happened inside the theater and what has happened since.

In the 62 pages of instructions given to the jury on Tuesday, Carlos A. Samour, Jr., the district court judge, again reminded jurors not to communicate with anyone or read anything about the case.

Samour told them not to consider Holmes’s potential punishment, which will be decided during a later phase, and he outlined what will happen to Holmes if the jurors accept the insanity defense, something he said he was providing for informational purposes only.

“If the defendant is found not guilty by reason of insanity, he will never again be tried on the merits of the criminal charges filed against him,” Samour wrote.

Ultimately, Samour said, jurors should “consider all the evidence in light of your experience in life.”

Jurors had three questions during the initial hours of deliberations on Wednesday, and they concluded deliberations late Wednesday afternoon without reaching a decision and left for the day. Once they reach a verdict, they will fill out forms declaring what they decide — which could include noting whether or not they were swayed solely by the insanity defense, according to sample verdict forms provided by court officials.

The trial was pushed back multiple times by delays, including arguments over evaluations of Holmes’s sanity, before jury selection finally began in January. It is taking place about half an hour away from the movie theater where the shooting occurred.

This particular trial is a relatively unusual saga among modern mass or active shootings, because after these kinds of incidents, the people opening fire are usually killed by police or at their own hands.

Shooting sprees in schools, shopping malls and other public places are stark, terrifying moments followed by mourning and questions about what happened. An official report typically follows, highlighting the gaps that could have been closed and the warning signs that could have been picked up.

Less commonly, these episodes are followed by trials like this one or the trial of Nidal Hasan, the Army psychiatrist sentenced to death for killing 13 people at the Fort Hood military installation in 2009. The recent shooting at a church in Charleston, S.C., appears likely to join this list, as the accused gunman has been indicted and charged with nine counts of murder.

For families and relatives, these trials can be painful, public reckonings with grief and loss. During the trial of Dzhokhar Tsarnaev, the now-convicted Boston Marathon bomber, families offered relentlessly painful testimonies. Yet the parents of one child killed in the blast and another who lost most of her leg asked the government not to seek the death penalty, solely to prevent appeals that could “prolong reliving the most painful day of our lives.” Tsarnaev was later sentenced to death by execution.

The Arapahoe County District Court where the trial is being held. (Brennan Linsley/AP)

Before the Aurora trial began, Holmes’s parents pleaded for their son’s life to be spared. They also criticized the idea of a trial that would force people to relive what happened three years ago.

“We do not know how many victims of the theater shooting would like to see our son killed,” Robert and Arlene Holmes wrote in a letter published by the Denver Post. “But we are aware of people’s sentiments. We have read postings on the Internet that have likened him to a monster. He is not a monster. He is a human being gripped by a severe mental illness.”

Instead, they argued that their son should be institutionalized or imprisoned for the rest of his life.

Prosecutors are seeking the death penalty in the case, and if Holmes is found guilty, the next step would be a penalty phase — lasting perhaps as long as a month — to determine whether he should be put to death.

This would be a rarity for Colorado, which has executed one inmate since the Supreme Court reinstated the death penalty in 1976. The state currently has just three inmates on its death row, and and as the Colorado Department of Corrections notes, a death row inmate would wait at least a decade before being executed (and probably longer).

[This post has been updated. It was originally published at 1:18 p.m.]