Most states disallow traps - they're indiscriminate devices that could harm people with legitimate reasons to go on your property, e.g. emergency workers.

what are they gonna do, arrest me?

They could arrest whoever owns that land.

they'd have to navigate the dungeon first. if they do that, then I guess me being arrested is their prize

They can summon your spirit and bind it to a prison cell (assuming you'll build a pyramid with traps).

Their fault for sending the clerics in before the rogue.

They're too late by definition: the dead have no need for emergency services.

There are no legitimate reasons to go on my property.

Nonsense. Property ownership is not absolute.

If the police can convince a judge that there is probably cause to believe that a crime is being committed on your property and to give them a warrant, that would be a legitimate reason to go to your property.

I don't believe any state specifically disallows traps and monsters. They just say how you're allowed to dispose of a body, not all the ways you can't. In other words, it's not an Air Bud situation. Anyway, just a joke, I don't have enough kobolds to populate a dungeon with (yet).

I don't think this is just a joke, it's a gross overstep by liberal governments. We should rally together as conservatives and libertarians to ensure that we get the burial that we deserve - big government has to go.