On Monday, December 16, the Gainesville School Board approved a measure allowing school resource officers access to rifles at their local middle and high schools to improve school safety. The rifle, a Colt 6920 M4 carbine, will be kept inside a safe, accessible only by the school resource officer for use in case of an active shooter situation. This decision came three days after an armed deputy at Arapaho High School in Colorado brought a swift end to a school shooting, cornering the 18-year-old gunman in the library while helping to evacuate students. Similar initiatives to place armed resource officers in schools, such as the NRA-recommended National School Shield Emergency Response Program, are being adopted across the country. As we saw last week in Colorado, the only thing that stops a bad guy with a gun is a good guy with a gun, and arming school resource officers is a great way to improve the safety of our children in schools.