Wis. Stat. § 51.39: Resident patients on unauthorized absence.

If any patient who is admitted, transferred, or placed under s. 55.06, 2003 stats., or s. 51.13, 51.15, 51.20, 51.35 (3), 51.37, or 51.45 (11) (b), (12) or (13) or ch. 55, 971, 975, or 980 is on unauthorized absence from a treatment facility, the sheriff or any other law enforcement agency in the county in which the patient is found or in which it is believed the patient may be present, upon the request of the director, shall take charge of and return the patient to the facility. The costs incident to the return shall be paid out of the facility’s operating funds and be charged back to the patient’s county of residence.