(1) Within 24 hours after receiving a report made or information obtained under section 11a, the county department shall commence an investigation to determine whether the person suspected of being or believed to be abused, neglected, or exploited is an adult in need of protective services. A reasonable belief on the part of the county department that the person is an adult in need of protective services is a sufficient basis for investigation. If an investigation pertains to an adult residing in an adult foster care facility licensed by the department of licensing and regulatory affairs, the county department shall provide the adult foster care licensee with the substance of the abuse or neglect allegations as soon as practicable after the beginning of the investigation. The licensee must have the opportunity to respond to the allegations, and the response must be included in the record.

  (2) Upon a request by the county department, local law enforcement officers shall cooperate with the county department in an investigation of suspected abuse, neglect, or exploitation. The investigation required by this section is not in place of an investigation by the appropriate police agency regarding suspected criminal conduct arising from the suspected abuse, neglect, or exploitation.

  (3) The investigation must include a determination of the nature, extent, and cause of the abuse, neglect, or exploitation; examination of evidence; identification, if possible, of the person responsible for the abuse, neglect, or exploitation; the names and conditions of other adults in the place of residence; an evaluation of the persons responsible for the care of the adult, if appropriate; the environment of the residence; the relationship of the adult to the person responsible for the adult’s care; an evaluation as to whether or not the adult would consent to receiving protective services; and other pertinent data.

  (4) The investigation must include an in-person interview with the adult. The county department shall conduct the interview by means of a personal visit with the adult in the adult’s dwelling or in the office of the county department. In attempting to conduct a personal visit with the adult in the adult’s dwelling, if admission to the dwelling is denied, the county department may seek to obtain a search warrant as provided in 1966 PA 189, MCL 780.651 to 780.659.

  (5) The investigation may include a medical, psychological, social, vocational, and educational evaluation and review.

  (6) In the course of an investigation, the county department shall determine if the adult is or was abused, neglected, or exploited. The county department shall make available to the adult the appropriate and least restrictive protective services, directly or through the purchase of services from other agencies and professions, and shall take necessary action to safeguard and enhance the adult’s welfare, if possible. The county department also shall collaborate with law enforcement officers, courts of competent jurisdiction, and appropriate state and community agencies providing human services, which services are provided in relation to preventing, identifying, and treating adult abuse, neglect, or exploitation. If the abuse, neglect, or exploitation involves substance use disorder, the county department shall collaborate with the local substance use disorder coordinating agency as designated by the office of recovery oriented systems of care in the department for a referral for substance use disorder services. The county department may petition for a finding of incapacity and to have a guardian or temporary guardian appointed as provided in section 5303 or 5312 of the estates and protected individuals code, 1998 PA 386, MCL 700.5303 and 700.5312, and may petition to have a conservator appointed as provided in section 5401 of the estates and protected individuals code, 1998 PA 386, MCL 700.5401, for a vulnerable adult. If a financial institution made the report of suspected abuse, neglect, or exploitation, the county department may inform that financial institution of the status of the investigation.

  (7) Upon completion of an investigation, the county department shall prepare a written report of the investigation and its findings. A copy of this written report shall be forwarded to the department upon request.

  (8) The county department may provide a copy of the written report to the prosecuting attorney for the county in which the adult suspected of being or believed to be abused, neglected, or exploited resides or is found.

  (9) A representative from the department, the department of state police, the department of attorney general, and the office of services to the aging, and an individual who is a representative of long-term care providers and is designated by the department of attorney general, shall meet and develop a state model protocol for investigating vulnerable adult abuse cases. A county prosecuting attorney, in cooperation with the local county department and local law enforcement agencies, may adopt a local protocol for investigating vulnerable adult abuse cases that is based on the state model protocol.