I watched a video where a group of Marines stormed a building that insurgents were holding out in, and one of the insurgents was lying in the corner pretending to be dead, and a marine laughed and said "Hey, this guys faking being dead" and shot him. This seems like a solid policy to me.
Something about this story that rings of being very untrue. First, if you "stormed a building" its an all out blazing battle right from the start. All hell is breaking loose. Than you discribe something turned into search detail "finding an insurgent playing dead", so they shot him. Plenty of time to laugh and say "Hey, this guy is faking being dead" before they shot him???? Not to mention someone is with them, inside a building and able to be in the way filming. Very unlikely to be happening in this manner. I don't I believe a word of the story they way you just told it. If they are storming and clearing, an assault on the building, thats much different than house to house seaches and inspections, that are policing actions, not combat offencsives.
If they stormed a building, they are not going to stop until, they are dead, wounded and not able to fight, or they surrender. If someone is faking to be dead, he is still fighting and under those circumstances, did the right thing shooting him. If he is faking being dead, he is capable of surrendering, so should be considered still in combat.
This isn't your local police, or the standard of law enforcement you expect from them, this is War and these are Marines in Combat. Two totally different situations, and totally different standards of firing weapons with deadly force. They are also facing a suicidal mentality, where they believe dying this way killing one these Marines is honorable. Thankfully, the Marines think, killing them first before they take out the Marine standing next to him, is just as honorable. As harsh as it seems, you try clearing the inside of a building, in close quarters, knowing in a heartbeat everyone could die, and not knowing if the dead guy may be faking or really dead. If he is really dead, shooting him again won't hurt him, and if he is faking, you probably got all of you killed, being Roy Rogers. You do state in your story the Marine confirmed he was faking, so the Marine did not just shoot the guy
with no reason. War is a nasty bussiness, and when you send Marines into a building facing many AK 47's, the enemy hasn't given up, and the mission is go in and kill them.