Too bad it wasn't on his sun visor!

Sorry there Joe, no booby traps for you.

'Spring Gun' laws, designed to prevent exactly the sort of thing that happened here, are on the books in all states. The theory is that you can't rig a device to do something that you legally couldn't do yourself. So since you can't legally kill, or even hurt someone just for their being on your property, you can't rig a gun to protect that vacant property.

This idiot shot himself, but historically there are many cases of 1) "Dern' kids always vandalizing ma farm!" 2) "Got it! I'll rig this shotgun to cover the door of my vacant farmhouse! That'll fix em." 3) Dern kid loses life/limb. 4) "Whaddya mean I'm being charged with attempted murder?".

So yeah, that snake pit? That's what we call a property hazard, that you as the owner would be liable for when little Jimmy falls in. Especially if it's visible from the outside and neighborhood kids know about it. Then it's also an attractive nuisance. Oubliette for burglars? Unlawful imprisonment. Poison darts? Murder/Attempted Murder/3rd Degree Cliche. Panic Room for you? Perfectly fine, perfectly legal (assuming it's up to code). Panic room to trap burglars? Unlawful imprisonment again. Electrified floors are probably ok if they are clearly marked and guests are properly warned... Think about, for example, an electric fence. Legal, but there should be signs.

Otherwise it's that whole 'murder' thing again.

Well, yes. I suppose you could put giant Tesla coils all around your house, constantly shooting out 15' lightning bolts. But then you're really entering into attractive nuisance land. Kids love a good show after all.

Not to mention actual nuisance, when your neighbors tire of the noise, constant smell of ozone and charred bird, and intermittent brown-outs.