Criminologist says he's never seen a failure of law enforcement like the Uvalde school shooting

According to Dr. Alex Del Carmen, an associate dean at Tarleton State University and criminologist, the biggest failure in the Uvalde school shooting was in the initial response. He says this is what police officers are trained to do and what they vow under oath to perform. He claims, though, that they weren't all educated for situations involving active shooters, which is another failing, after reading this article.