A Pennsylvania state police Cpl. Richard Schroeter was charged with five counts of reckless endangerment on Tuesday in the shooting death of a fellow police officer, according to the Philadelphia Inquirer.

Schroeter, a 20-year veteran of the police force, allegedly shot and killed Trooper David Kedra by accident in September while teaching five officers on a new weapon at a training facility in Plymouth Township.

“Schroeter was discussing the trigger mechanics when he pulled the trigger on his duty-issued firearm,” the District Attorney’s office and State Police said in a statement.

According to the statement, the grand jury concluded that “Schroeter breached routine, yet critical safety protocol by failing to visually and physically check to ensure his weapon was unloaded, failing to obtain confirmation from another that his firearm was not loaded, and failing to point his weapon away from the direction of everyone present.”