Wis. Stat. § 302.15: Activities off grounds.

The wardens and superintendents of the state prisons, and all wardens and superintendents of county prisons, jails, camps and houses of correction enumerated in ch. 303, may take inmates away from the institution grounds for rehabilitative and educational activities approved by the department and under such supervision as the superintendent or warden deems necessary. While away from the institution grounds an inmate is deemed to be under the care and control of the institution in which he or she is an inmate and subject to its rules and discipline.