I pushed someone out of my house once, closed and locked the door and told him not to come back. About six hours later the cops showed up with assault charges. It was dismissed, but I spent four hours being booked and fingerprinted at our local jail. It took me three years to realize that despite the supposed presumption of innocence until proven guilty in the U.S. legal system, that I still had to go through a fairly involved process to expunge the arrest record. I could have done the expungement earlier, but I figured dismissed means dismissed. I knew I was arrested, but I didn't know there was an arrest record requiring expungement until a potential employer brought it to my attention.
The lesson was if you want someone out of your house, call the cops yourself.