Novel idea, but how do you handle disagreement between the first person who can see an imminent threat and the person in the back of the stack in a way that doe

Novel idea, but how do you handle disagreement between the first person who can see an imminent threat and the person in the back of the stack in a way that doesn't get the first guy through the door killed more often, doesn't just become a rubber stamp, blanket approval "to be on the safe side", and offers improved outcomes compared to relying on the training and judgment of the individual in front with a gun?