I know it's illegal to possess a handgun in the city of Chicago, as well as Madison. I wonder if a city could ban guns outright, ala Unforgiven? But Illinois State law has a provision that makes self-defense an affirmative defense for such restrictions, as long as one is within their residence or fixed place of business. So, while technically, some cities like Chicago or Wilmette ban handguns within their limits, it wouldn't be prosecuted if used for self defense. In addition to OWM's point about the 14th Amendment, many state constitutions have similiar provisions anyway. IL's constitution contains the following: "Subject only to the police power, the right of the individual citizen to keep and bear arms shall not be infringed"