Wis. Stat. § 66.0508: Collective bargaining.

(1) In this section, “local governmental unit” has the meaning given in s. 66.0506 (1).

(1m) Except as provided under subch. IV of ch. 111, no local governmental unit may collectively bargain with its employees.

(2) If a local governmental unit has in effect on June 29, 2011, an ordinance or resolution that is inconsistent with sub. (1m), the ordinance or resolution does not apply and may not be enforced.

(3) Each local governmental unit that is collectively bargaining with its employees shall determine the maximum total base wages expenditure that is subject to collective bargaining under s. 111.70 (4) (mb) 2., calculating the consumer price index change using the same method the department of revenue uses under s. 73.03 (68).