The prosecutor in the case of James Holmes, suspected in the shooting deaths of 12 moviegoers in Colorado, said Monday that the prosecution has an "enormous amount of evidence," but that she would not call it a "slam dunk."
"There is no such thing as a slam dunk case ... we would never presume that it would be a slam dunk. We will work very hard on this case to prosecute it," Arapahoe County District Attorney Carol Chambers said.
Holmes -- who faces the possibility of life in prison or the death penalty for allegedly carrying out one of the most deadly mass murders in U.S. history -- might have to plead insanity, according to veteran Seattle attorney and legal analyst Anne Bremner.
"The insanity defense appears to be the only option," Bremner told The Huffington Post. "We don't hold those who don't have the requisite criminal intent criminally accountable."
"Competent psychiatrists will most likely first evaluate his competency to stand trial," Bremner added. "We don't know if he has any mental illness as yet. Many of us assume he does or he wouldn't have committed his horrific acts but he could just be bad -- a natural-born killer -- and competency is a very low standard."
Holmes, a 24-year-old former doctoral student at the University of Colorado, Denver, has been held on first-degree murder charges in the shooting spree at a midnight screening of "The Dark Knight Rises."
Police arrested Holmes in the early morning hours of July 20, minutes after the shooting in the sold-out theater in Aurora, Colo. Holmes, dressed in ballistic gear and armed with an assault rifle and three other guns, set off gas canisters before opening fire, police said. A dozen theater patrons were killed and 58 others were wounded.
Holmes will face formal charges from prosecutors on July 30 and Chambers said her office is considering the death penalty against him.
The prosecution could, however, face a challenge in aiming for the death penalty. There is always the possibility that the defense could claim insanity, which, if successful, would make Holmes ineligible for the death penalty.
"Maybe his best defense is to argue at sentencing you can't execute the mentally (if he is) ill. That it is cruel and unusual punishment under the Eighth Amendment," Bremner said.
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Public defender Tamara Brady was assigned to the case, presumably after Holmes indicated he could not afford to hire a lawyer. Brady appeared in court with Holmes on Monday for an initial hearing. Her client seemed sleepy or dazed and often had his eyes shut during the proceeding. Brady has yet to comment on her client’s behavior in court and the defense has thus far been reluctant to speak on the case.
"He looks insane, his acts are those of an insane person, ergo he is insane," Bremner said.
The veteran attorney cautions that there is a long road ahead for the defense.
"His defense will not be that easy," she said. "In fact, his attorneys face nearly insurmountable difficulties in a court of law and even more so in the court of public opinion. No one even wants to talk about James Holmes, let alone acknowledge that he has a right to a defense and a trial."
Bremner said Holmes' attorney may well be an "attorney for the damned," due to the number of things she would need to overcome at trial. The biggest challenge for the defense may be the allegation by police that Holmes spent months planning and stockpiling guns, thousands of rounds of ammunition and head-to-toe ballistic gear.
"He planned, he schemed [and] he purchased. He stockpiled, he booby-trapped, he created mass mayhem and death. He shot a six-year-old who just learned how to swim. He took 12 souls and shattered the lives of hundreds more. He showed no remorse. He remained silent and he wouldn't cooperate with the authorities," Bremner said.
"When I was a DA, we would say, 'well he didn't hold up a telephone pole with a banana,'" she said. "He robbed a bank with a gun."