Wis. Stat. § 167.31

(1) Definitions. In this section: (a) “Aircraft" has the meaning given under s. 114.002 (3) . (b) “Encased" means enclosed in a case that is completely zipped, snapped, buckled, tied or otherwise fastened with no part of the firearm exposed. (bg) “Family member of the landowner" means a person who is related to the landowner as a parent, child, spouse, or sibling. (bn) “Farm tractor" has the meaning given in s. 340.01 (16) . (c) “Firearm" means a weapon that acts by force of gunpowder. (cm) “Handgun" has the meaning given in s. 175.60 (1) (bm) . (d) “Highway" has the meaning given under s. 340.01 (22) . (dm) “Implement of husbandry" has the meaning given in s. 340.01 (24) . (e) “Motorboat" has the meaning given under s. 30.50 (6) . (em) “Peace officer" has the meaning given in s. 939.22 (22) . (et) “Private security person" has the meaning given in s. 440.26 (1m) . (f) “Roadway" has the meaning given under s. 340.01 (54) . (fg) “Stationary" means not moving, regardless of whether the motor is running. (fm) “Street" means a highway that is within the corporate limits of a city or village. (fr) “Transmission facility" means any pipe, pipeline, duct, wire, cable, line, conduit, pole, tower, equipment, or other structure used to transmit or distribute electricity to or for the public or to transmit or distribute communications or data to or from the public. (g) “Unloaded" means any of the following: 1. Having no shell or cartridge in the chamber of a firearm or in the magazine attached to a firearm. 2. In the case of a cap lock muzzle-loading firearm, having the cap removed. 3. In the case of a flint lock muzzle-loading firearm, having the flashpan cleaned of powder. 4. In the case of an electronic ignition muzzle-loading firearm, having the battery removed and disconnected from the firearm. (h) “Vehicle" has the meaning given in s. 340.01 (74) , but includes a snowmobile, as defined in s. 340.01 (58a) , an all-terrain vehicle, as defined in s. 340.01 (2g) , an electric scooter, as defined in s. 340.01 (15ps) , and an electric personal assistive mobility device, as defined in s. 340.01 (15pm) , except that for purposes of subs. (4) (c) and (cg) and (4m) “vehicle" has the meaning given for “motor vehicle" in s. 29.001 (57) .

(2) Prohibitions; motorboats and vehicles; highways and roadways. (a) Except as provided in sub. (4) , no person may place, possess, or transport a firearm, bow, or crossbow in or on a motorboat with the motor running, unless one of the following applies: 1. The firearm is unloaded or is a handgun. 2. The bow does not have an arrow nocked. 3. The crossbow is not cocked or is unloaded. (b) Except as provided in sub. (4) , no person may place, possess, or transport a firearm, bow, or crossbow in or on a vehicle, unless one of the following applies: 1. The firearm is unloaded or is a handgun. 2. The bow does not have an arrow nocked. 3. The crossbow is not cocked or is unloaded. (c) Except as provided in sub. (4) , no person may load a firearm, other than a handgun, in a vehicle or discharge a firearm or shoot a bolt or an arrow from a bow or crossbow in or from a vehicle. (d) Except as provided in sub. (4) (a) , (bg) , (cg) , (e) , (fm) , and (g) , no person may discharge a firearm or shoot a bolt or an arrow from a bow or crossbow from or across a highway or within 50 feet of the center of a roadway. (e) A person who violates pars. (a) to (d) is subject to a forfeiture of not more than $100.

(3) Prohibitions; aircraft. (a) Except as provided in sub. (4) , no person may do any of the following: 1. Place, possess, or transport a firearm, bow, or crossbow in or on a commercial aircraft, unless the firearm is unloaded and encased or unless the bow or crossbow is unstrung or is enclosed in a carrying case. 2. Place, possess, or transport a firearm, bow, or crossbow in or on a noncommercial aircraft, unless the firearm is unloaded and encased or the firearm is a handgun or unless the bow or crossbow is unstrung or is enclosed in a carrying case. (b) Except as provided in sub. (4) , no person may load or discharge a firearm or shoot a bolt or an arrow from a bow or crossbow in or from an aircraft. (c) A person who violates par. (a) or (b) shall be fined not more than $1,000 or imprisoned not more than 90 days or both. (3m) Prohibitions; transmission facilities. (a) Except as provided in sub. (4) (b) and (h) , no person may intentionally discharge a firearm in the direction of a transmission facility. (b) A person who violates par. (a) and causes damage to a transmission facility is subject to a forfeiture of not more than $100. (c) In addition to any forfeiture imposed under par. (b) , the court shall revoke any hunting license under ch. 29 that is issued to the person found in violation for a period of one year. (d) In addition to any forfeiture imposed under par. (b) and the revocation required under par. (c) , the court shall enter a restitution order that requires the defendant to pay to the owner of the transmission facility the reasonable cost of the repair or replacement of the transmission facility.

(4) Exceptions. (a) Subsections (2) and (3) do not apply to any of the following who, in the line of duty, place, possess, transport, load or discharge a firearm in, on or from a vehicle, motorboat or aircraft or discharge a firearm from or across a highway or within 50 feet of the center of a roadway: 2. A member of the U.S. armed forces. 3. A member of the national guard. 4. A private security person who meets all of the following requirements: a. He or she holds either a private detective license issued under s. 440.26 (2) (a) 2. or a private security permit issued under s. 440.26 (5) . b. He or she holds a certificate of proficiency to carry a firearm issued by the department of safety and professional services. c. He or she is performing his or her assigned duties or responsibilities. d. He or she is wearing a uniform that clearly identifies him or her as a private security person. e. His or her firearm is in plain view, as defined by rule by the department of safety and professional services. (ag) Subsection (2) (b) does not apply to a firearm, bow, or crossbow that is placed or possessed on a vehicle that is stationary. (am) 1. Subsections (2) (a) , (c) and (d) and (3) (a) and (b) do not apply to a peace officer who, in the line of duty, loads or discharges a firearm in, on or from a vehicle, motorboat or aircraft or discharges a firearm from or across a highway or within 50 feet of the center of a roadway. 2. Subsection (2) (b) does not apply to a peace officer who places, possesses or transports a firearm in or on a vehicle, motorboat or aircraft while in the line of duty.