In Gist v. State, 766 P.2d 1149, 1151 (Wyo. 1988), an undercover narcotics officer testified that he had simulated smoking marihuana while taking part in a drug transaction involving the defendant. Gist, 766 P.2d at 1149. The officer testified, however, that he had never actually used illegal drugs. 766 P.2d at 1150. The defense requested that the trial court allow it to present extrinsic evidence of the officer's prior drug use to contradict the officer's statement. Id. The trial court refused to allow the defendant to present the extrinsic evidence to the jury. 766 P.2d at 1151-52. On appeal, the Court held that extrinsic evidence of the officer's prior drug use was admissible to refute his statement that he had not used drugs because that issue was material to the case. 766 P.2d at 1152.