331.20  EMERGENCY OR PUBLIC SAFETY VEHICLES AT STOP SIGNALS OR SIGNS.
   (a)   The driver of any emergency vehicle or public safety vehicle, when responding to an emergency call, upon approaching a red or stop signal or any stop sign shall slow down as necessary for safety to traffic, but may proceed cautiously past such red or stop sign or signal with due regard for the safety of all persons using the street or highway. 
   (b)   Except as otherwise provided in this subsection, whoever violates this section is guilty of a minor misdemeanor.  If, within one year of the offense, the offender previously has been convicted of or pleaded guilty to one predicate motor vehicle or traffic offense, whoever violates this section is guilty of a misdemeanor of the fourth degree.  If, within one year of the offense, the offender previously has been convicted of two or more predicate motor vehicle or traffic offenses, whoever violates this section is guilty of a misdemeanor of the third degree.
(ORC 4511.03)