W. Va. Code § 33-2-3A

(a) In addition to the authority granted to the fraud unit created in article forty-one of this chapter and to the workers' compensation fraud and abuse unit previously transferred to the commissioner pursuant to section one-b, article one, chapter twenty-three of this code, the commissioner has the authority to conduct investigations whenever he or she has cause to believe that a violation of any provision of this chapter or of chapter twenty-three of this code has been or is being committed.

(b) Employees designated by the commissioner are permitted to operate vehicles owned or leased by the state displaying Class A registration plates when engaged in carrying out the investigative duties assigned to the commissioner by this chapter.