The officer should have already had his pistol in hand. Once he saw the suspect was armed and he pointed the rifle at him, it was incumbent on the officer to get off a shot. No doubt he would have missed, but the shooter would have been distracted and the SS could engage without needing a green light from a supervisor.
It's hard to climb with a pistol in hand. Once a rifle is pointed at you, stopping to draw is asking to get shot. Best thing might be to get under cover to draw your weapon safely.
A better issue might be, if the SS had a guy who could shoot that place, why not call in that you have been told of a possible shooter and that you are going to check it out, which should have had the SS eyeballing that position.
“Tolerance is the virtue of the man without convictions.” GK Chesteron
Inde muagdhe Aes Sedai misain ye!
Deus Vult!
*MySmiley*