A former Uvalde, Texas, school district police officer pleaded not guilty to the 29 counts against him on Thursday as families of the Robb Elementary School victims looked on.
Two teachers and 19 students were killed in the May 24, 2022, mass shooting. Law enforcement waited some 77 minutes at the scene before breaching a classroom and killing the gunman.
Former Uvalde school district police officer Adrian Gonzales faces 29 charges of abandoning and failing to protect children: 19 for the 19 children killed and 10 for the children who survived in classroom 112.
The indictment alleges that despite having time to respond to the shooting, Gonzales failed to act to impede the gunman and failed to follow active shooter training by not advancing toward the gunfire.
MORE: Former Uvalde school police chief charged with 10 counts of 'abandoning and endangering' Robb Elementary survivorsOver 30 survivors and victims' families watched in the courtroom on Thursday as Gonzales pleaded not guilty.
The families included the parents of 10-year-old victim Tess Mata, the parents of 9-year-old victim Jackie Cazares and the parents of survivor Khloie Torres.
"It's not that we want to be here -- we just feel like we have to," Tess' mom, Veronica Mata, told ABC News after the hearing. "We're here 'cause we have to be here for Tess."
Tess' dad, Jerry Mata, said while he feels more than two officers should have been indicted, he hopes this is the start of accountability.
"The emotions right now are so high," he said. "We've been waiting for this for a long time."
Gonzales' defense attorney, Nico LaHood, told reporters, "We have not seen any evidence that would lead us to believe that Mr. Gonzales is guilty of these allegations. ... All he did was show up to try to help those children."
"There was over 370 officers there. We have not seen or even heard of a theory of why Mr. Gonzales is being singled out," LaHood said.
Gonzales is due to return to court on Sept. 16.
The former school district police chief, Pete Arredondo, who was the on-site commander the day of the shooting, was arrested last month on the same charges as Gonzales. He has also pleaded not guilty.
MORE: Inside Uvalde football's transformative, emotional season that uplifted a grieving townThe indictment alleges that, after hearing shots fired, Arredondo failed to identify the situation as an active shooter, failed to respond as trained, and instead, called SWAT, thereby delaying the response by law enforcement.
The indictment also alleges he chose to negotiate with the gunman instead of engaging; failed to timely provide keys and breaching tools; failed to determine if the classroom door was locked; failed to follow the school district's active shooter policy; and failed to develop an immediate action plan.
In a recorded interview with investigators one day after the shooting, Arredondo said he did not view himself as the incident commander, contrary to the active shooter plan he devised.