(CBS/AP) CENTENNIAL, Colo. - Colorado prosecutors filed 24 counts of murder charges Monday against James Eagan Holmes, the former neuroscience student accused of killing 12 people and injuring 58 others at an Aurora movie theater, The Associated Press reports.
Prosecutors also filed 116 counts of attempted murder against Holmes, who Aurora police said booby trapped his apartment with the intent to kill any officers responding there the night of the theater attack.
Holmes, 24, was not expected to enter pleas on Monday. He ultimately could verbally enter a plea, or his attorneys could enter it for him.
Unlike Holmes' first court appearance July 23, Monday's hearing was not televised. At the request of the defense, District Chief Judge William Sylvester barred video and still cameras from the hearing, saying expanded coverage could interfere with Holmes' right to a fair trial.
Last week, Sylvester allowed a live video feed that permitted the world its first glimpse of the shooting suspect. With an unruly mop of orange hair, Holmes appeared bleary-eyed and distracted. He did not speak.
Investigators said Holmes began stockpiling gear for his assault four months ago and bought his weapons in May and June, well before the shooting spree just after midnight during a showing of the Batman film "The Dark Knight Rises."
The four guns retrieved from the shooting were purchased legally at three Colorado gun stores between May 22 and July 6, CBS News correspondent Bob Orr reports. A federal law enforcement source told CBS News that Holmes spent $15,000 fortifying his arsenal online. Authorities found a shipping label from BulkAmmo.com in a dumpster near Holmes' apartment, the source said. EBay was the vendor Holmes used to purchase some body armor, the source said.
Holmes was arrested by police outside the theater. Analysts said that means it's likely there's only one main point of legal dispute between prosecutors and the defense.
"I don't think it's too hard to predict the path of this proceeding," said Craig Silverman, a former chief deputy district attorney in Denver. "This is not a whodunit. ... The only possible defense is insanity."
One development over the weekend brought more grief. A woman who was critically wounded and whose 6-year-old daughter was killed suffered a miscarriage because of the trauma, her family said Saturday. Ashley Moser's daughter, Veronica Moser-Sullivan, was the youngest person killed in the attack.
Under Colorado law, defendants are not legally liable for their acts if their minds are so "diseased" that they cannot distinguish between right and wrong. However, the law warns that "care should be taken not to confuse such mental disease or defect with moral obliquity, mental depravity, or passion growing out of anger, revenge, hatred, or other motives, and kindred evil conditions."
Experts said there are two levels of insanity defenses.
Holmes' public defenders could argue he is not mentally competent to stand trial, which is the argument by lawyers for Jared Loughner, who is accused of killing six people in 2011 in Tucson, Ariz., and wounding several others, including Rep. Gabrielle Giffords. Loughner, who has pleaded not guilty to 49 charges, has been diagnosed with schizophrenia and is undergoing treatment at a Missouri prison facility in a bid to make him mentally fit to stand trial.
If Holmes' attorneys cannot convince the court that he is mentally incompetent, and he is convicted, they can try to stave off a possible death penalty by arguing he is mentally ill. Prosecutors will decide whether to seek the death penalty in the coming weeks.
Attorneys were also expected to argue Monday over a defense motion to find out who leaked information to the news media about a package the former neuroscience graduate student allegedly sent to his psychiatrist at the University of Colorado Denver.
Authorities seized the package July 23, three days after the shooting, after finding it in the mailroom of the medical campus where Holmes studied. Several media outlets reported that it contained a notebook with descriptions of an attack, but Arapahoe County District Attorney Carol Chambers said in court papers that the parcel hadn't been opened by the time the "inaccurate" news reports appeared.
Sylvester has tried to tightly control the flow of information about Holmes, placing a gag order on lawyers and law enforcement, sealing the court file and barring the university from releasing public records relating to Holmes' year there. A consortium of media organizations, including CBS News, is challenging Sylvester's sealing of the court file.
On Friday, court papers revealed that Holmes was seeing a psychiatrist at the university. But they did not say how long he was seeing Dr. Lynne Fenton and if it was for a mental illness or another problem.
The University of Colorado's website identified Fenton as the medical director of the school's Student Mental Health Services. An online resume listed schizophrenia as one of her research interests and stated that she sees 10 to 15 graduate students a week for medication and psychotherapy, as well as five to 10 patients in her general practice as a psychiatrist.
Authorities said Holmes legally purchased four guns before the attack at Denver-area sporting goods stores — a semiautomatic rifle, a shotgun and two pistols. To buy the guns, Holmes had to pass background checks that can take as little as 20 minutes in Colorado.