Wis. Stat. § 343.435: License not to be used as security.

(1) No person may require or accept an operator’s license, chauffeur’s license, occupational license, instructional permit or any other license or permit issued under this chapter as security.

(2) Any person violating this section may be required to forfeit not less than $20 nor more than $100.

(3) This section does not apply to the action by a state, county, city, village or town of requiring or accepting a license or permit when such action is authorized by some other provision of law.