How do we review a finding of law by a federal district court?

We review de novo a district court's findings of law. United States v. McConney, 728 F.2d 1195, 1201 (9th Cir.) (en banc ), cert. denied, 469 U.S. 824, 105 S.Ct. 101, 83 L.Ed.2d 46 (1984). We review a district court's findings of fact for clear error. Kruso v. International Tel. & Tel. Corp., 872 F.2d 1416, 1421 (9th Cir.1989). In determining the question of liability of the United States under the Federal Tort Claims Act, the district court is obligated to apply the law of the state in which the accident occurred. 28 U.S.C. 1346(b). Therefore, in this case we review the district court's application of California law.