Tennessee Code Title 52. Department of Disability and Aging § 52-4-102

If a person admitted under court order leaves a facility without authority, then the facility must immediately notify the court regardless of the length of the person's absence.  If the person is taken into custody, then the person may be returned to the facility upon an order by the court.  After thirty (30) days' absence, the person may be dropped from the facility's records.  A return after thirty (30) days' absence is a new admission.  A person's absence beyond thirty (30) days does not limit the power of the court to order the person's return to a facility under this section.