Wis. Stat. § 133.17: Prosecutions.

(1) The department of justice or the district attorney shall institute, manage, control and direct, in the proper county, all prosecutions for violations of this chapter. When prosecuting violations of this chapter, the department of justice shall have and exercise all powers conferred upon district attorneys.

(2) Any district attorney bringing any action under this chapter shall serve copies of all pleadings on the department of justice within 3 days from the time of filing. If the department of justice brings any action under this chapter, it shall serve copies of all pleadings on the district attorney of the county where the action is brought within 3 days from the time of filing.