Since they change regularly, I suppose I can say that I have distinctive colored stickers on my pistols, which
generally can't be seen while in the holster. (Because of the way I was sitting @ Starbuck's one day, Paul saw one that was over the muzzle.)
If I have the misfortune to meet up with one of Jeri's Kids & s/he makes a false report (as happened here), I think that when I ask the officers to have her/him describe the Evil Pistol & all s/he can say is essentially "it's black, it's evil", then I (very carefully & slowly, depending on which arrangement of stickers we're talking about) show them how my pistol is unusual & how visible these markings are, they'll see pretty quick that it's the other person they need to ticket/arrest (for making a false report, etc.).
(Show them
after they've asked the 'victim', just in case there's an anti-carry officer who might feed answers.)
(And if anyone reads this & thinks they can guess, or just say "there are stickers", I don't think that'll be enough proof for the police... or judge.
What color? Where are they? What design? All of that changes.)
I should also say that I carry Glocks, so am not worried about damaging the finish.
Oh, and if you cover the muzzle, it's a lot easier to remove the sticker BEFORE shooting @ the range than trying to get the baked-on residue off afterwards. (DAMHIK*) Then again, it's something you'll only do once, kinda like getting your hand too high behind the slide of a semiauto, though not as painful.
*
Don't Ask Me How I Know