Just about any handgun can cause permanent damage if fired without hearing protection but there does seem to be evidence that the louder calibers make it worse.Well I hope you guys here were earmuffs 7/24 if you are so worried about hearing damage in a SD situation cause if you pack any serious gun it is going to go bang and might hurt your ears.
Does that mean folks shouldn't use magnums for self-defense or for LE? I guess some people might make that decision, but if they do, I would think that it would be wiser to make the decision for reasons other than potential hearing damage.
The point is, of course, that people should make their decisions based on the facts. I get the impression that some folks think that it would be better to conceal the facts as long as doing so gets others to make decisions that match their own.