What is the standard of review applied to a district court's denial of a defendant's proposed jury instruction?

An apparent intra-circuit split of authority confounds the standard of review this court applies to a district court's denial of a defendant's proposed jury instruction. See United States v. Frank, 956 F.2d 872, 878 (9th Cir.), cert. denied, --- U.S. ----, 113 S.Ct. 363, 121 L.Ed.2d 276 (1992); but see United States v. Gomez-Osorio, 957 F.2d 636, 642 (9th Cir.1992) (suggesting that there is no true conflict in our decisions, and that "the question turns on the issue for review"). The apparent conflict is of no relevance here. In this instance, the district court refused appellants' proffered instructions on the ground that those instructions were contrary to law. Accordingly, we apply a de novo standard of review.