Updated 7:58 PM ET
(CBS/AP) CENTENNIAL, Colo. - Attorneys for the suspect in the Colorado movie theater shootings said Thursday their client is mentally ill and that they need more time to assess the nature of his illness.
James Holmes' lawyers made the disclosure at a court hearing in suburban Denver where news media organizations were asking a judge to unseal court documents in the case.
Holmes, a 24-year-old former Ph.D. student at the University of Colorado, Denver, had the familiar, dazed demeanor that he has had in previous court appearances.
Holmes is accused of going on a July 20 shooting rampage at a midnight showing of the latest Batman movie in Aurora, killing 12 people dead and injuring 58 others.
Defense attorney Daniel King made the revelation about Holmes as he argued defense attorneys need more information from prosecutors and investigators to assess their client.
"We cannot begin to assess the nature and the depth of Mr. Holmes' mental illness until we receive full disclosure," he said.
King said Holmes sought out university psychiatrist, Lynne Fenton, for help. He did not elaborate. A hearing was scheduled for Aug. 16 to establish whether there is a doctor-patient relationship between Fenton and Holmes. CBS News has learned Fenton reported concerns about Holmes to University of Colorado police. The university has retained attorneys for both Dr. Fenton and the police officer.
The hearing was held because CBS News, the Associated Press, and 19 other news organizations are asking Chief District Judge William Sylvester to make available documents that could provide details about Holmes and the July 20 attack.
Holmes did not have to be in court, CBS news correspondent John Blackstone reports, but his lawyers made no requests to have his presence waived.
Arapahoe County prosecutors said earlier that releasing documents could jeopardize their investigation. Holmes' attorneys want to ensure he receives a fair trial.
Sylvester's order sealing documents includes the case file, which makes it impossible for observers to understand prosecution and defense arguments on motions that are referenced by number only.
Sylvester on July 23 also issued a gag order that bars officials at the University of Colorado from responding to public records requests concerning Holmes.
The judge said doing so would jeopardize the county's investigation. Aurora officials have cited the order in declining to speak about the city's response to the shootings.
"It is performing our watchdog role to look at the process and try to assess for the public how the police have handled the case and assembled the evidence and assure for the defendant and the public that things are being conducted open and fairly," said Gregory Moore, editor of The Denver Post. "It goes way beyond what's necessary to protect the defendant's right to a fair trial."
Court documents, which include search warrants, inventories of evidence collected by police and police interviews with witnesses can be an important source of information for the public.
Little is known about how police say Holmes prepared for the shooting, or how they say he rigged his nearby apartment with explosives. Aurora Police Chief Daniel Oates has said the explosives were designed to kill anybody who entered, including first-responders.
Steven D. Zansberg, an attorney representing the news media consortium, said the judge should at least explain which documents have been sealed and why.
In Colorado, this type of legal battle has been seen before.
In 2007, an Arapahoe County judge sealed an indictment in the case of a missing 6-year-old girl whom authorities determined had been dead for at least two years before her father, Aaron Thompson, reported her missing. The state Supreme Court ordered the indictment unsealed in 2008, allowing the public to learn the charges against Thompson. Thompson was convicted of fatal child abuse in 2009.
When Los Angeles Lakers player Kobe Bryant faced sexual assault charges in Vail in 2003, it took a media challenge to unseal an affidavit in which police laid out their case for an arrest. Bryant maintained his innocence, and prosecutors dropped the case in 2005.
A news media challenge led to last year's release of an arrest affidavit in a sexual assault case involving former Denver Broncos cornerback Perrish Cox. Cox was acquitted in March.
Defense attorneys and prosecutors routinely ask judges to keep some documents sealed, often because the documents contain information a jury won't hear at trial, said Denver criminal defense attorney Daniel Recht, who also argues First Amendment cases.
But Moore noted that some Colorado judges have sealed entire court dockets under the argument that the mere fact of media coverage will damage a case.
In his ruling to unseal documents in the Cox case, Douglas County District Judge Paul A. King rejected that notion. "There can be no presumption that everyone in the jury panel will read, follow and find important the media accounts in this case," King wrote.