If I am on the ground with two "unknown" assailants trying to kick the [censored] out of me, that seems like a bad situation to be in, judgement call.
Only takes a second for things to go VERY wrong, one sharp toed boot to the temple and .. . . . . . . or tweaker pulling a knife. . .. . . .
I don't' take using lethal force lightly, however, if I feel my life or others is in danger (and that includes possbile debilitating injuries) and I use my weapon, the perp is not "walking away with a limp".