Prosecutors are considering pursuing a death penalty case against James Holmes, the alleged gunman accused of a movie theatre rampage last Friday that left 12 dead and 58 wounded.
A decision on charging Holmes, 24, with capital murder has not yet been made, but Arapahoe County District Attorney Carol Chambers told reporters today she is talking with victims and their family members about it.
There are currently only four people on Colorado's death row, and only one person has been executed in that state since 1976.
Nevertheless, experts expect prosecutors to seek the death penalty when Holmes is formally charged later this week.
Holmes is expected in court today for a preliminary hearing.
Members of the Aurora community are anxiously awaiting today's hearing, the first time Holmes has been seen in public since his arrest following a deadly rampage at a midnight screening of the "The Dark Knight Rises" on Friday.
"He has harmed so many people," Oates said. "Not only the victims, but all of their extended families. So I think it will be very hard," Police Chief Daniel Oates said.
Oates also told ABC News that Holmes' parents have remained silent.
"They're not talking to us right now," he said. "Maybe that will change, but right now they are not talking to us."
The suspect will be brought to court from his jail cell at Arapahoe County Jail through an underground tunnel.
The court appearance is expected to be brief and will start the clock on the 72-hour deadline for the district attorney to file formal charges at an arraignment where Holmes will enter his plea.
The police chief told ABC News that his team is getting significant help from the FBI's behavioral analysts in trying to figure out what could have changed Holmes from a promising young student to a suspect in one of the largest mass shootings in U.S. history.
Authorities found a computer and Batman poster and a Batman mask from the comic books in his apartment, according to sources, ABC News reported.
"I was struck by one source today who said that this 'was really like a mad scientist, really like a villain in a movie,'" Thomas said. "We are being told by sources that they have found the computer, and also a poster of Batman."
ABC News learned this weekend that Holmes apparently applied online for a membership at a local gun range last month. On the application, he apparently said he did not use drugs and was not a convicted felon. When Glenn Rotkovich, who owns the Lead Valley Range in Byers, Colo., called him to follow up, he said, he got a "bizarre," Batman-inspired voicemail message.
He told his staff not to allow Holmes into the club if he showed up for an orientation.
ABC News early Sunday obtained exclusive video and photos of Holmes as a thin teenager in an oversized shirt from a science camp six years ago at Miramar College in San Diego.
"Over the course of the summer, I've been working with a temporal illusion. It's an illusion that allows you to change the past," Holmes said in the video.
By most accounts, Holmes lived the life of a normal teen, with a particular interest in science.
The video shows him being introduced at the seminar as someone whose "goals are to become a researcher and to make scientific discoveries. In personal life, he enjoys playing soccer and strategy games and his dream is to own a Slurpee machine."