Prosecutors filed a court document listing aggravating factors they plan to raise in a possible death penalty phase of the trial.
Holmes is charged with more than 160 counts, including murder and attempted murder. Prosecutors say he spent months buying guns and thousands of rounds of ammunition, donned police-style body armor and opened fire in a crowded Aurora theater during a midnight showing of the latest Batman movie on July 20. Twelve people were killed and 70 injured.
Prosecutors are seeking the death penalty.
One of the aggravating factors prosecutors listed Friday is the death of 6-year-old Veronica Moser-Sullivan, the youngest of dead. Another says the slayings were "especially heinous, cruel or depraved."
The other factors suggest Holmes acted with malice and "extreme indifference to the value of human life" and accuse him of knowingly putting other people at risk.
Prosecutors said they could add to the list. They also said they might ask to use audio and video recordings of Holmes with other people in the Arapahoe County jail as evidence.
Also Friday, defense lawyers suggested again that they might challenge the constitutionality of state laws on the death penalty and insanity pleas.
Holmes' attorneys said in a written motion that overlapping elements of the laws could violate Holmes' protection against self-incrimination, his right to present evidence in his own defense, and other provisions of the U.S. and state constitutions.
Holmes' lawyers tried to raise their constitutionality questions in March, but Judge William Sylvester refused to consider them. Prosecutors had not yet said whether they would ask for the death penalty, so Sylvester said questions about the laws were only speculative at the time.
Holmes was widely expected to enter an insanity plea but so far has not.
His lawyers told Sylvester in March they had too many questions about the insanity and death penalty laws to give Holmes sound advice, and that Holmes declined to enter a plea. Sylvester entered a not guilty plea on Holmes' behalf but said Holmes could ask to change to an insanity plea later.
Sylvester has withdrawn from the case, citing his workload as the chief judge in a busy district. He appointed District Judge Carlos Samour Jr. to take over.
Defense lawyers revived their questions in a motion asking Samour for more time to respond to a revised list of cautions Holmes would have to sign if he wanted to plead insanity or if he wanted to enter a standard plea of not guilty but still introduce expert testimony about his mental condition.
One of the cautions says Holmes must cooperate with doctors during a mandatory mental health evaluation or he won't be able to present mitigating evidence about his mental state if he is convicted and a jury decides whether he should be executed.
That caution is at the core of the constitutional questions by the defense, said Karen Steinhauser, a former prosecutor and now an adjunct law professor.
It's not clear how cooperation is defined, she said, and the question hasn't been tested in court since the laws were changed to their present form in the late 1990s.
Sylvester had issued a similar list of cautions in March. Samour revised it this week and told lawyers to submit objections or suggestions by Monday. Holmes' lawyers said they needed at least another week, but Samour gave them only until Wednesday, saying that was enough time.