Quinn Cunningham is a SWAT team officer and firearms instructor in greater Denver, Colorado. Having personally responded to a school shooting, he knows the limits of law enforcement in an active-shooter situation.

To help prevent school shootings in his state, Cunningham now trains teachers and school administrators to carry concealed weapons at school through a program called Faculty/Administrator Safety Training and Emergency Response, or FASTER.

“An armed society is a polite society,” he says.

In the video above, Cunningham tells his story and explains how the FASTER program works.