The gunman in the mass shooting that killed five and wounded 17 at a Colorado Springs LGBTQ nightclub appeared before a judge via video link from jail on Wednesday.
Anderson Lee Aldrich, 22, had been in hospital since their arrest on Sunday morning.
The advisement hearing took place via video link, with the jailed defendant appearing in handcuffs and a jail uniform.
During the shooting, the gunman was tackled by Richard Fierro, a decorated war veteran who fought in both Iraq and Afghanistan, in a successful effort to stop further bloodshed at Club Q in Colorado's second-largest city.
The defendant was seen slumped in a wheelchair, displaying facial injuries and appeared to have difficulty speaking.
Defence lawyers with the Colorado State Public Defender's office said in court filings on Tuesday that the defendant identifies as non-binary, prefers they/them pronouns and will be referred to in court filings with the “Mx” honorific.
El Paso County District Attorney Michael Allen said that would have no bearing on how he would prosecute the case, including whether to charge Mx Aldrich with hate crimes.
Police initially held Mx Aldrich on charges of five counts of first-degree murder and bias crimes stemming from the Saturday night shooting spree.
Those charges were not discussed in the brief hearing, during which defence lawyers asked to receive a copy of the arrest warrant.
Mr Allen said after the hearing that he expected to file formal criminal charges before the defendant's next court hearing, tentatively scheduled for December 6.
In the meantime, Mr Allen said his office would continue to ask that Mx Aldrich be held without bail.
Reuters contributed to this report