Any person charged with the violation of any rule, regulation, restriction, or ordinance of said City, which regulates, restricts, or defines the time or place of parking vehicles in the City of Vergennes or prescribes any traffic regulations may within three days from the date of such charge by a statement signed by such person, admit such violation and waive issuing of any process and a trial by jury or hearing, and may voluntarily pay to said Traffic Court of said City the penalty herein prescribed; provided, however, that whenever in the opinion of said Court, the gravity of the offense requires a fine in excess of the above penalty, such Court may refuse to accept such signed statement and penalty and shall then make complaint to the proper prosecuting officer of said City, or to the State's Attorney of the County. In such event, such signed statement and penalty shall be returned to the offender and shall not be considered as an admission or used as evidence in any trial in any court in this State.