Help evicting squatting abusive brother.

(Montana eviction question. All names are anonymous and names will be substituted. No real names used.)

My mom lived in a trailer across the street from my other brother we shall call “john”, she let my oldest criminally insane brother “jack” live there, he moved into the back room.

My mom died and left the house to my other brother, “john’ who lives across the street. “Jack” continued to stay there paying nothing. My sister “jane” then moved in, she pays rent and taxes. She is here with her daughter who in 12.

“Jack” has a long history of abuse and violence both sexual and otherwise. He has had multiple convictions under his name and is dodging child support by working under the table. His ex left him due to abuse of both kids. He also molesting my sister when she was little.

“Jack” has been very violent and abusive, turns off the power to the house when he is told to follow rules, threatens people with physical harm, breaks their stuff, threatens towing their vehicles, making the landlord kick him out etc. He is in good graces with the landlord as he is a manipulative and affictatious man.

We 4 all signed an agreement 2 years ago that the home would remain in “johns” name and family would live there.

He “jack” owes 900 dollars in electricity, pays nothing, eats up all the food, wont apply for foodstamps, and continues to work under the table for some guy while continuing to act like he owns the place. He isnt on the lease, the trailer isnt in his name, and the only thing that is? Is the electricity.

We are affraid of violence and harm. He has been told to leave 3 times due to him not following any agreements made and due to his tyrannical nature. He refuses to leave.

We want him out, but don’t want shit busted and people hurt. What can we do to get him out for good? He is getting more aggressive and he has told others he is trying to get the trailer out from under us through the landlord, when its owned by my brother “jack”

We have again sent him notice and told him to leave many times but he won’t. I dont even know how to report his actions as they are all done in a way as to avoid such things, he breaks stuff in rage then claims it wasn’t him. Threatens people and the denies it. Turns off the power then when the cops are in their way? Turns it on and says it never happened. He is a sociopathic person.

What can we do? What steps must be taken? No one wants to be hurt. I am very inexperienced with this and need help getting him out asap.