65 ILCS 5/3.1-35-35: Mayor or president pro tem; temporary chairman.

(a) If the mayor or president is temporarily absent because of an incapacity to perform official duties, but the incapacity does not create a vacancy in the office, the corporate authorities shall elect one of their members to act as mayor or president pro tem. The mayor or president pro tem, during this absence or disability, shall perform the duties and possess all the rights and powers of the mayor or president but shall not be entitled to vote both as mayor or president pro tem and as alderperson or trustee.

(b) In the absence of the mayor, president, acting mayor or president, or mayor or president pro tem, the corporate authorities may elect one of their members to act as a temporary chairman. The temporary chairman shall have only the powers of a presiding officer and a right to vote only in the capacity as alderperson or trustee on any ordinance, resolution, or motion.