Securing doors is a tenet of school safety drills, and the issues displayed here are raising alarms among experts and politicians. Ferking expanded on the historical circumstances that influenced this design, and the recent evolutions put into practice.

The tragedy at Columbine led to an overhaul in school construction, said Ferking. Today, most new classrooms lock from inside via a key or thumb turn. Furthermore, most exterior doors are locked during school hours, except during drop-off and pick-up, he continued.

“I can promise you, [that school] is not the only one in this country that you can’t lock the doors from the inside,” said Mo Canady, the executive director of the National Association of School Resource Officers.

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