The mayor shall have the power to release any person imprisoned for violation of any city ordinance; he may, if he sees fit, appoint a pardon board of three persons, consisting of the superintendent of the house of correction and such inspectors thereof as he may select. In case such board be appointed all petitions for release from the house of correction shall in the first instance be addressed to said board and shall be by them forwarded to the mayor, with a report of their findings and recommendations.
65 ILCS 20/21-6