Welf. & Inst. Code, § 4119

(a) The State Department of State Hospitals shall investigate and examine all nonresident persons residing in a state hospital and shall cause these persons, when found to be nonresidents as defined in this chapter, to be promptly and humanely returned under proper supervision to the states in which they have legal residence. The department may defer that action by reason of a patient’s medical condition.

(b) Prior to returning the judicially committed nonresident to his or her proper state of residency, the department shall do either of the following:

(1) Obtain the written consent of the prosecuting attorney of the committing county, the judicially committed nonresident person, and the attorney of record for the judicially committed nonresident person.

(2) In the department’s discretion request a hearing in the superior court of the committing county requesting a judicial determination of the proposed transfer, notify the court that the state of residence has agreed to the transfer, and file the department’s recommendation with a report explaining the reasons for its recommendation.

(c) The court shall give notice of the hearing to the prosecuting attorney, the judicially committed nonresident person, the attorney of record for the judicially committed nonresident person, and the department, no less than 30 days before the hearing. At the hearing, the prosecuting attorney and the judicially committed nonresident person may present evidence bearing on the intended transfer. After considering all evidence presented, the court shall determine whether the intended transfer is in the best interest of, and for the proper protection of, the nonresident person and the public. The court shall use the same procedures and standard of proof as used in conducting probation revocation hearings pursuant to Section 1203.2 of the Penal Code.

(d) For the purpose of facilitating the prompt and humane return of these persons, the State Department of State Hospitals may enter into reciprocal agreements with the proper boards, commissions, or officers of other states or political subdivision thereof for the mutual exchange or return of persons residing in any state hospital in one state whose legal residence is in the other, and it may in these reciprocal agreements vary the period of residence as defined in this chapter to meet the requirements or laws of the other states.

(e) The department may give written permission for the return of a resident of this state confined in a public institution in another state, corresponding to a state hospital of this state. When a resident is returned to this state pursuant to this chapter, he or she may be admitted as a voluntary patient to an institution of the department as designated by the Director of State Hospitals. If he or she has a mental health disorder and is a danger to himself or herself or others, or he or she is gravely disabled, he or she may be detained and given care and services in accordance with the provisions of Part 1 (commencing with Section 5000) of Division 5.