What are the elements of self-defense when a defendant is charged with assaulting a federal officer?

The magistrate judge had jurisdiction pursuant to 18 U.S.C. Sec. 3401. The district court had jurisdiction pursuant to 18 U.S.C. Sec. 3402. We have jurisdiction pursuant to 18 U.S.C. Sec. 1291; see also United States v. Forcellati, 610 F.2d 25, 28 (1st Cir.1979) ("While there is ... no express provision for ... the defendant to appeal from a judgment of the district court affirming a magistrate's conviction, such appeals have been allowed apparently as a matter of course."), cert. denied, 445 U.S. 944 (1980).

We review the findings of facts under the clearly erroneous standard and the application of law to the facts under the de novo standard. United States v. McConney, 728 F.2d 1195, 1200-01 (9th Cir.1984), cert. denied, 469 U.S. 824 (1984).

The defense of self-defense applies (1) where a defendant reasonably believes that his use of force is necessary to defend against the immediate use of unlawful force by another; and (2) where the defendant uses no more force than appears reasonably necessary in the circumstances. United States v. Span, 970 F.2d 573, 576 (9th Cir.1992) (listing elements of self-defense when defendant is charged with assaulting a federal officer), cert. denied, 113 S.Ct. 1283 (1993). The burden does not shift to the government to disprove self-defense beyond a reasonable doubt unless the defendant first produces sufficient evidence to support a rational finding of self-defense. United States v. Jackson, 726 F.2d 1466, 1468-69 (9th Cir.1984); see also United States v. Bowman, 720 F.2d 1103, 1105 (9th Cir.1983) (holding that a defendant is not entitled to a self-defense instruction unless sufficient evidence supports the defense).