>Thinking he was the first officer to arrive and wanting to waste no time, Arredondo believed that carrying the radios would slow him down. One had a whiplike antenna that would hit him as he ran. The other had a clip that Arredondo knew would cause it to fall off his tactical belt during a long run.

There are children being shot and he's worried some radio antenna's gonna smack him as he ran, or that one might fall off his belt? Bite your lip and put up with the antenna whipping you, and/or put the other radio on your belt, hoping that it doesn't fall off, and if it does, at least you can say you tried.

I realize we're talking split seconds, but it doesn't take long to clip a radio, as you're walking, to your belt.

One imagines the chief has further responsibilities involving incident command for which a radio is rather useful.

"To Arredondo, the choice was logical. An armed killer was loose on the campus of the elementary school. Every second mattered. He wanted both hands free to hold his gun, ready to aim and fire quickly and accurately if he encountered the gunman."

Why didn't he make sure his radio worked for him?