Upon the granting of franchises to traction companies or motor or bus transportation companies throughout this state for the use of streets, roads, and highways for the transportation of passengers, it must be provided, as one of the considerations for such use of the public highways, that such traction companies or motor or bus transportation companies shall carry free as passengers on all regular cars and busses, policemen and firemen when on duty and in uniform.
R.C. § 4951.54