One of the worst domestic acts of violence in American history, the school shooting in Uvalde, Texas, still horrifies us even all these months later. And part of the reason we continue to be horrified is that we still don’t know the full scope of the utter failures of law enforcement that took place that day.

Law enforcement on the scene ignored their training (or, worse, weren’t properly trained), leaving children and teachers trapped in classrooms with the killer. The fallout has been intense – firings from the top down, a town turned upside down, and even bipartisan legislation aimed at preventing another incident like it in the future.

CNN obtained the one and only interview then-police chief Pete Arredondo gave to the Texas Department of Public Safety, giving us a glimpse into his logic that day, and it only further shows how flawed and troubling his decisions were that day.

“Once I realized that was going on, my first thought is that we need to vacate. We have him contained – and I know this is horrible and I know it’s [what] our training tells us to do but – we have him contained, there’s probably going to be some deceased in there, but we don’t need any more from out here,” Arredondo said.

His decision to treat the gunman as a barricaded subject and not confront him effectively left all the students and teachers in Classrooms 111 and 112 for dead. It was one of many times he did not follow the training and protocol for an active shooter.

Arredondo stuck with that choice for over an hour, even when he thought he heard the gunman reloading and after it was confirmed children were trapped – injured and alive as well as dead – with the shooter.

It should come as no secret that his decision violated the training his department supposedly received, and it flies in the face of what we know should be the proper response. You can evacuate, but you have got to apprehend – or at least stop – the shooter in that situation before it becomes an even deadlier situation. And because Arredondo decided against proper protocol there, the result was as infuriating as it was tragic.

Records supplied to CNN by DPS show Arredondo took required active shooter training at least three times, including in the December before the massacre. The specific course he took then instructs officers to “isolate, distract and neutralize” the attacker. It reminds officers “First responders to the active shooter scene will usually be required to place themselves in harm’s way and display uncommon acts of courage to save the innocent.”

The decision-making that happened on May 24, 2022, was equal parts cowardly and ignorant, and Arredondo’s words, now that we can see them, verify that.