Former Uvalde school district police officer Adrian Gonzales pleaded not guilty Thursday to multiple child-endangerment charges stemming from the botched response to the Robb Elementary School shooting that killed 19 schoolchildren, and two teachers and injured many others.

Former Uvalde Consolidated Independent School District police officer Adrian Gonzales arrives at the Uvalde County Courthouse on Thursday in Uvalde, Texas. Eric Gay/Associated Press

It was the first time any law enforcement officer had faced the families of the victims in court since the 2022 massacre. Co-defendant Pedro “Pete” Arredondo, the former school district police chief, waived his appearance and was absent from court. He has also pleaded not guilty.

A Uvalde County grand jury indicted Gonzales and Arredondo late last month. Prosecutors allege that both men, by their inaction and actions, were among the first to arrive at the scene but left children vulnerable to the attack by a lone shooter. The charges are unprecedented in Texas.

“We are in uncharted territory,” said Gonzales’s attorney Nico LaHood, who added that he has yet to see the state’s evidence against his client. “All he did was show up to help those children.”

Inside the courthouse, security was tight and those attending the hearing had their bags checked twice. A framed painting of the 21 people who were killed in the shooting hung from the wall at the north entrance, where deputies rifled through purses and passed a wand over attendees. Inside the courtroom, the families and their attorneys filled six rows.

The much-criticized Uvalde County District Attorney Christina Mitchell was not present.

It took more than 70 minutes after the shooter first opened fire on the school for law enforcement to confront the gunman. About 40 minutes of that was spent looking for keys and equipment, evacuating adjacent classrooms and trying to negotiate with the shooter.

The U.S. Justice Department issued a scathing 575-page report that singled out local police commanders and state law enforcement for not immediately entering the classroom and killing the gunman. Attorney General Merrick Garland said that “lives would have been saved” if officers had responded quickly.

Gonzales never approached the classroom where the shooting was occurring, prosecutors allege.

The state will have to prove that the former officer knowingly acted or failed to act in a way that led to the deaths of 19 children and injuries of 10 others. Arredondo is charged with 10 counts – or one for each wounded child.

No other officers, including city police who arrived seconds after the two defendants, have faced any charges. Arredondo’s attorney did not respond to a request for comment.

State Judge Sid Harle, based in San Antonio, presided over the hearing as Gonzales said little more than a soft “not guilty” during the proceeding. He was flanked on either side of the gallery by a battery of attorneys and security personnel including Texas Rangers and Uvalde County Sheriff’s deputies.

Gonzales’s legal team said after the hearing that they don’t know how the special prosecutor singled out their client and tied the evidence to the charges. They are hiring additional investigators to review an extraordinary amount of evidence, they said.

The defense team also did not discount the possibility of requesting a venue change if they believed their client could not get a fair trial in Uvalde. But they said they do not have enough information yet.

“There is a horrible monster responsible for the deaths of these children,” LaHood, Gonzales’s attorney, said in front of a gaggle of reporters and cameras. “And it’s not Adrian Gonzales.”

Most of the families quickly left the courthouse after the hearing, but a few stayed to listen to Gonzales’s attorneys.

Brett Cross, whose son, Uziyah Garcia, was slain in the shooting, said he looked Gonzales in the face as he walked by him outside the court. All he saw, he said, was cowardice.

“If you put your life higher than that of children, then you’re a monster as well,” Cross said.