Dear dogs, please don't piss on the Christmas lights

Just had a gentleman come into the store, with a grim look on his face.

"You've got a dangerous situation in front of your store!" he said. "I just saw a dog peeing on the Christmas lights wrapped around your tree and he got an electric shock!"

Every once in a while, I get a guy in off the street who immediately launches into some story, and I thought this was a joke.

"Good!" I exclaimed.

He looks at me like I'm scum.

"What if a young kid gets shocked?"

Hmmmm. I see he's not joking, but now I can't resist.

"Even better!" I say, looking at him askance.

After he left, customer Aaron suggested I should put up a sign.

"Dear Dogs, (and kids),

Do not piss on this tree or you will be electrocuted. (All legal ramifications now null and void.)"