The Ohio Rules of Evidence, specifically Evid. R. 601(C ) describes persons incompetent to testify in court proceedings. One of these incompetents is:
An officer, while on duty for the exclusive or main purpose of enforcing traffic laws, arresting or assisting in the arrest of a person charged with a traffic violation punishable as a misdemeanor where the officer at the time of the arrest was not using a properly marked vehicle as defined by statute or was not wearing a legally distinctive uniform as defined by statute.
Thus if a police officer is on duty to enforce traffic laws, then, if he wants to testify against the person that he alleges was breaking them, the officer must be in the proper uniform of the day for his department and he must be in a marked police cruiser. If not, the court will not allow him to testify in court and the evidence against the accused goes up in smoke. That usually results in a dismissal of charges.
