(a) For purposes of Section 207(f), an elected office and the office of Chief of Police become vacant when, in a quo warranto action or other applicable proceeding as may be established by state law, a court has found that:
(1) the incumbent is physically or mentally incapacitated due to illness, injury or other reason such that he or she cannot perform the duties of the office;
(2) the incumbent was so incapacitated for at least 90 consecutive days prior to the filing of the application with the Office of the California Attorney General for leave to sue in quo warranto or, if the application was not legally required, any other act commencing litigation under this subsection; and
(3) there is reasonable cause to believe that the incumbent will not be able to perform the duties of the office for the remainder of the term of office.
(b) If the City Clerk, after investigation, has reason to believe that all of the conditions set forth in subsection (a) exist, the City Clerk, on behalf of the City, shall initiate, or cause to be initiated, litigation by filing an application for leave to sue in quo warranto with the Office of the California Attorney General or by following any other applicable procedure as may be established by state law. Litigation under this section, in quo warranto or as otherwise provided by state law, may also be brought by any person authorized to do so by state law.