Marjory Stoneman Douglas High School student David Hogg came to the defense of the armed resource officer who never entered the Parkland, Florida school where 17 people were killed in a mass shooting, asking, “Who wants to go down the barrel of an AR-15, even with a glock?”

In an interview Saturday on MSNBC, Mr. Hogg insisted that the officer, Scot Peterson, “just like every other police officer out there at heart — is a good person.”

Mr. Peterson, who has been widely criticized for failing to enter the school and confront suspect Nikolas Cruz, resigned on Thursday.

CNN reported on Friday that three other sheriff’s deputies had not entered the building when Coral Springs, Florida police arrived on scene.