That’s why and who they suing per the article. I am sure there is more to it. The article did not go in depth. If you are on private property and breaking the law in Colorado they have the right to use force to remove the person. If the person is a threat to anyone else (he was) then they could use more force and the Castle Doctrine could even protect you if deadly force was used depending on the situation. Since they are in civil court and no charges seem to have been filed I think legally the force was considered justified? Involuntary manslaughter would be the criminal charge if not. I’m not a lawyer though.