Contrary to Police Chief Arredondo's claims that the police lacked firepower, police had at least two long guns with them early in the shooting. And four ballistic shields.
One of the police officers on scene had a daughter in the classroom where the shooter was. Another officer's wife was also in the classroom bleeding from a gunshot wound. This officer would be escorted away by other officers.
While at least one officer is believed to have suggested the police go in, the officers instead waited around saying they didn't have orders to do so.
The police had a Halligan tool with them, but never used it on the door. The door apparently wasn't even locked to begin with, and the police didn't try to open the door until they breached over an hour later.