Can municipalities adopt and enforce ordinances prohibiting the discharging of a gun within the municipality?
Yes. While municipalities are generally prohibited from regulating firearms more stringently than state law, the statutes expressly provide that municipalities may enact ordinances restricting the discharging of firearms. Wis. Stat. sec. 66.0409(3)(b). However any ordinance or resolution that restricts the discharge of a firearm does not apply and may not be enforced if the actor's conduct is justified or, had it been subject to a criminal penalty, would have been subject to a defense described in sec. 939.45. Id.
Section 66.0409(2) prohibits, with certain exceptions, any city, village, town or county from enacting an ordinance or adopting a resolution that regulates the "sale, purchase, purchase delay, transfer, ownership, use, keeping, possession, bearing, transportation, licensing, permitting, registration or taxation of any firearm or part of a firearm, including ammunition and reloader components," unless the ordinance or resolution is the same as or similar to, and no more stringent than, a state statute. "Firearm" is defined to mean "a weapon that acts by force of gunpowder." Wis. Stat. sec. 167.31(1)(c). As a result of this prohibition, municipalities may adopt or continue to enforce ordinances regulating the use of a firearm only if the ordinance has a statutory counterpart. Any municipal ordinances which attempt to regulate firearms differently or more stringently than state law are invalid and unenforceable.