Mont. Code § 53-21-186
When a mental health facility conditionally releases a patient committed to its care, it is not liable for the patient's support while conditionally released. Liability transfers to the legal guardian, parent, or person under whose care the patient is placed when conditionally released or to any other person legally liable for the patient's support. The local office of public assistance in the county where the patient resides or is found is responsible for providing relief and care for a conditionally released patient who is unable to be self-supporting or who is unable to secure support from the person under whose care the patient was placed on convalescent leave, like any other person in need of relief and care, under the public assistance laws.
§ 53-21-186, MCA