Nine months after the Colorado theater shooter was sentenced to life in prison, some victims are returning to the same courtroom in hopes of holding the company that owns the suburban Denver movie theater accountable for not doing more to prevent his bloody rampage.

In a civil trial starting Monday in state court, 28 victims' families say Century Theaters should have had armed guards at the packed opening of the Batman film "The Dark Knight Rises" and alarms that would have sounded when James Holmes slipped into the darkened auditorium through an emergency exit and opened fire, killing 12. Jurors will be asked determine if, in an age of mass shootings, the theater should have foreseen the possibility of an attack.

The families will argue Cinemark knew the midnight blockbuster would attract at least 1,000 people and should have had guards patrolling the parking lot, where they might have seen Holmes suiting up in head-to-toe body armor in his car. The lawsuit says theater employees failed to check doors, lacked closed-circuit television cameras that would have allowed them to spot trouble and did not intervene as victims lay wounded and dying in the aisles.

Theaters across the country had extra security for the July 20, 2012, premiere, and the Century 16 theater in Aurora typically had guards Friday, Saturday and Sunday nights, said New York attorney Marc Bern, who is representing 27 of the families. The premiere fell on a Thursday.

"We believe if these precautions had been in place, the shooting would have been deterred and prevented," he said.