§47-157.3.

§47-157.3.
   
   Any person or persons suffering damages from the claimed negligent
   acts of any of such departments, their officers, servants, employees,
   or agents, arising from the operation of the vehicles, motorized
   machinery, or equipment so insured is hereby authorized to maintain an
   action to collect damages against the insurer. The insurer may not
   plead as a defense in any action involving insurance purchased by the
   authority of this act the governmental immunity of either the State of
   Oklahoma, the State Highway Department, the State Department of
   Agriculture, or the State Department of Public Welfare, or any other
   subdivision of state government.