Notwithstanding any provisions within this chapter, the tax administrator shall have the authority for cause shown to abate any taxes assessed pursuant to § 44-49-9.1 and § 44-49-10. Cause shown shall include a request for an abatement by the department of attorney general for dealers who have cooperated with law enforcement authorities in the investigation and prosecution of violations of the Rhode Island Controlled Substances Act, chapter 28 of Title 21.