10.08.070   Unauthorized persons shall not direct traffic.
   No person other than an officer of the police department or members of the fire department or a person authorized by Chapter 10.28 of this title or other law shall direct or attempt to direct traffic by voice, hand or other signal, except that persons may operate, when and as herein provided, any mechanical pushbutton signal erected by order of the city traffic engineer. (Prior code § 25.01.008)