In this day and age, you almost can't even shoot an intruder that's already come into your house, so I'm sure that electric fence is a lawsuit waiting to happen. Even if it was just a lower-voltage like the type used for electric fences for cattle and such, I could imagine an intruder climbing the fence, getting a mild shock that scares him, getting hurt in the fall, and suing.
Heck, a few years ago, this sickening story happened. A lady at work has an old home in the family down in southern Virginia somewhere. It's a tall, two story house with an observation deck on the top. There was a telescope mounted up there. One night a guy tried to climb up the side of the house to steal the telescope, lost his grip, and fell off the house. He got hurt and sued!
Last I heard, the homeowner's insurance actually PAID for this fool! And the argument was that the telescope served as an ENTICEMENT!! If it wasn't up there, he wouldn't have tried to climb up and get it, and wouldn't have gotten hurt, so, not his fault!
Now I could understand a case where this argument could be used for a kid drowning in a neighbor's swimming pool or duck pond that didn't have a fence around it, as a kid won't necessarily have the common sense to stay away. But we're talking grown adults here!
I wonder how good old fashioned barbed-wire fences would be treated nowadays? There used to be a lot of farms around here, and those were the norm. But these days, most of them are gone, or the few that are left are just old, forgotten things deep in the woods that have mostly collapsed. I wonder though, if you put up a barbed-wire fence and someone cut themselves on it, if you'd get in trouble?
