Cop catches elderly couple doing it in public, but never expected their explanation

Earl leans over and asks his wife, "Do you remember the first time we had sex together over 50 years ago?

"We went behind the village tavern where you leaned against the back fence and I made love to you."

"Yes," Maxine says, "I remember it well."

"OK," her husband responds, "How about taking a stroll around there again and we can do it for old times' sake?"

"Oh Earl, you old devil, that sounds like a crazy, but good, idea!"

A police officer sitting in the next booth heard their conversation and, having a chuckle, he thinks to himself, "I've got to see these two old-timers having sex against a fence. I'll just keep an eye on them so there's no trouble."

So he follows them. The elderly couple walks haltingly along, leaning on each other for support aided by walking sticks.

Finally, they get to the back of the tavern and make their way to the fence. The old lady lifts her skirt and the old man drops his trousers. As she leans against the fence, the old man moves in.

Then suddenly they erupt into the most furious sex that the policeman has ever seen. This goes on for about 10 minutes while both are making loud noises and moaning and screaming. Finally, they both collapse, panting on the ground.

The policeman is amazed. He thinks he has learned something about life and old age that he didn't know.

After about half an hour of lying on the ground recovering, the old couple struggle to their feet and put their clothes back on. The policeman, still watching, thinks to himself, "This is truly amazing, I've got to ask them how they do it ..."

So, as the couple passes, he says to them, "Excuse me, but that was something else. You must've had a fantastic sex life together. Is there some sort of secret to this?"

Shaking, Earl is barely able to reply, "Fifty years ago that wasn't an electric fence.''