What is the standard of review used by the 9th Circuit to determine whether a party was properly denied a jury instruction?

We review the sufficiency of the evidence "by looking at it in the light most favorable to the government." United States v. Pisello, 877 F.2d 762, 764 (9th Cir.1989). The appellate court must determine whether any rational trier of fact could have found beyond a reasonable doubt that the government had established all of the essential elements of the crime. Id.

This circuit has not clearly established what standard of review it uses to determine whether a district court properly denied a party's request for a jury instruction. United States v. Whitehead, 896 F.2d 432, 434 (9th Cir.1990). At times we have applied an abuse of discretion standard and at other times we have reviewed the district court's decision de novo. Id. We need not become entangled in this apparent conflict as the district court did not err under either standard.