Granite district using military M-16s to defend schools
As of 2012, the likelihood of any school having a shooting is once in every 13,870 years, Perrodin said, though he noted school shootings are increasing.
Johnson said that for any officer anywhere to carry a rifle at all times is not practical. He described the rifles as a tool.
"You use them when you need them and then you put them away," Johnson said.