We have a stream behind our house, separating us and our neighbor behind us. He's an awesome dude who keeps it clean. Got real mad at some asshole throwing coffee cups into the stream so he installed some cameras. Well, recently some asshole has been throwing bags of dog poo in there. He showed us the videos, and I've been on the lookout. Saw the culprit with his wife and kid and two dogs just now while we're walking our dog.
"HI! Please stop throwing your dogs poop in the stream back there. Kids play there".
Guy : I don't do that.
Wife : we don't do that. (indignant)
Me: yeah, you do, we have video.
Wife: I'd love to see that please, because we don't do that.
I show them the video, clear as day, of the guy chucking bags of dog shit into the stream.
Wife: (dangerously calm and quiet) I'm sorry. I did not know about this.
Guy: (sheepish) I'm sorry.
That dude is getting fucking chewed out right now, I guarantee that. Wife was pissed