Will James Holmes Be Found Not Guilty By Reason Of Insanity? ‘The Dark Knight’ Shooter's Trial Is Finally Underway

While the sentencing phase of the Boston Marathon bombings trial continues on Monday in Boston, another high-profile trial is just getting underway in Colorado. After years of delays, the trial of James Holmes, the "Dark Knight" shooter accused of killing 12 people and injuring dozens more in a darken movie theater, is finally beginning. Holmes has pleaded not guilty by reason of insanity, and faces the death penalty.

The crux of the trial is, of course, Holmes' sanity: His defense team will have to prove that Holmes, who was a 24-year-old grad school dropout at the time of the shooting, did not understand his actions and their moral consequences. Even if Holmes suffered from mental illness — and part of the reason why the trial was delayed so long was because of extensive psychological testing — he could still be found "sane" by the jury.

Holmes is accused of entering a midnight screening of The Dark Knight Rises on July 20, 2012, in Aurora, Colorado, and opening fire on the audience. The city of Aurora is less than 30 miles from Columbine, the site of another mass shooting — the Columbine High School massacre that left 14 people dead, including the two gunmen, and sparked a national debate on gun control in America.

12 people were killed in the shooting, and 70 more were wounded. Nearly 60 people endured gunshot wounds.

Before opening fire on the crowd as The Dark Knight Rises played on the screen, Holmes allegedly set off canisters of tear gas as a decoy. Witnesses and authorities have stated that he was dressed in ballistic gear, and some witnesses have said they thought Holmes was part of a promotional event when he first entered the theater through the emergency exit door.

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Although Holmes has pleaded not guilty, his lawyers have admitted that he was the shooter. Now, it's his sanity that will determine the case — and his life. But whether or not the insanity defense will work in Holmes' favor is still up in the air, according to legal experts.

The legal bar is set pretty high for Holmes' lawyers: The Associated Press reports that insanity cases tend to work only 25 percent of the time in felony trials, and have been even less successful in cases of homicide. Grant Duwe, a Minnesota corrections researcher and author of Mass Murder in the United States: A History, also told the AP that of the 74 mass shootings that have gone to trial, just three were found insane.

The fact that there still doesn't seem to a motive behind the violent shooting may give credence to Holmes' insanity defense. Holmes' lawyers have said their client was in the midst of a psychotic breakdown. And from the meager evidence released to the public (much of the evidence in this case has been kept under seal), it appears Holmes' was under duress and suffering from mental illness months before the shooting, dropping out of graduate school and isolating himself from his peers and coworkers.

"We see these common threads through mass public shooters and it describes the individual who commits this type of violence," Duwe told The Denver Post. "But I don't think it necessarily explains why they do what they do."

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That question of "why" is expected to be answered during the trial, but legal analysts have agreed that a motive may never be clear or concrete. Although the prosecution doesn't need a solid motive in the end, some experts believe the senselessness of this shooting massacre could sway the jury into believing Holmes was truly insane when he stormed the movie theater the night of July 20, 2012. "Nobody who isn't nuts would do this — so that's a hurdle the prosecution has to overcome," former Colorado prosecutor Bob Grant recently told Colorado Public Radio. Like the Tsarnaev case, Holmes will receive life imprisonment if he doesn't get the death penalty. Even if he is not found legally insane, the jury could spare him his life. In addition to the motive behind the gruesome shooting, the jurors are expected to look at the months-long preparation Holmes took, including buying weapons and ordering gear online. There, the prosecution is likely to try to build part of their case: Can an insane person also premeditate murder in such a way? Images: Getty Images (2)