In February 1988, Harless, then 15 years old, made headlines as the gunman in a different school shooting.

He and a friend both came to Pinellas Park High School with stolen .38-caliber revolvers. Administrators confronted the boys in the cafeteria. There was a struggle. By the end, Harless had shot a student teacher in the leg, fired three bullets into an administrator’s abdomen and shot an assistant principal in the head at point-blank range, which later killed the man. …

Harless and McCoy planned to run away from their homes on that day in February 1988. They stole the guns for protection. But, he says, he never planned to shoot anyone. …

Asked what he thinks might prevent shootings: “Nothing,” he said. “At the end of the day, there are no preventable measures. It’s human nature.”