Father In Law Moved And Won't Quit Doing Illegal Stuff.

I can't "tell the story" without appearing to be angry/biased and I really need some good advice here so I'm just going to give you the facts as bullet points:

• Five years ago, my father-in-law gifted my wife 170k if we would sell our house and buy a different property with two houses so he could live with us.
• He regularly visits a prostitute.
• He brought drugs from his old state and wanted my friends to buy them (they don't use).
• He buys "auto parts" from China that are actually NFA items.
• He has other weapons that have no serial numbers.
• He was wearing a political hat one day and my wife wouldn't let him go on a boat ride with us if he was going to wear his hat. He responded by walking into his house, getting a shotgun, and killing one of the mating pair of geese that liked to wander around our shore line. He then left it's body in the yard by our dock so that we'd know what he had done.
• Once he found out that a friend and I were talking to the state about getting a distilling license, he went an ordered a still online and had it sent right to our property. He's never done anything with it but he tells everyone he knows that he has a still.
• We live on the coast. You don't get to touch the coastline in my state without a lot of red tape. In a corner of our property is a salt marsh that is held together with briar, scrub trees, and sawgrass. After I told him about the state laws, he took his tractor and ripped it all up. If the county notices, it's a $5k/day fine.

Him and I got into it the other night and I told him we would be asking him to leave. He said he wants his $170k back. I said it was a gift (we have the documentation) and that 5 years of rent (he has a one bedroom house and a 7 car garage full of his stuff) on a 5 acre peninsula with salt water access with consume most of that money.

I'm not sure how relevant this is but when I told my wife about the argument and that we both needed to go over there and talk to him she responded "I really don't feel like having a gun pulled on me right now".

Additionally, we have to lock everything up now. My wife is scared that he's going to plant drugs or illegal weapons in our cars or home and two days ago, while my wife and kid were gone, he walked around the property randomly firing his gun. I assumed this was a warning for me but he texted my wife and said there were hunting dogs on the property...which is totally possible. I just didn't see any.

Yeah so how do we get rid of this guy? Is he a tenant? No idea how any of this works.