solely under state law.” United States v. Cormier, 220 F.3d 1103, 1111 (9th Cir.2000). We have extended this principle to the context of tribal law, holding that the admissibility of evidence in federal court is determined without regard to tribal law. Male Juvenile, 280 F.3d at 1023 (“[W]e reject the contention that tribal law should govern the admissibility of statements in federal court. Federal law governs federal proceedings.”); see also United States v. Hornbeck, 118 F.3d 615, 617 (8th Cir.1997) (“Federal, not tribal or state, law governs the admissibility of evidence” in the district court). For many years, we left unresolved the question whether state or federal law governed the reasonableness of seizures, see, e.g., United States v. Clawson, 831 F.2d 909, 913 (9th Cir.1987) (<HOLDING>); United States v. Contreras-Diaz, 575 F.2d
holding that the stop of a car was permissible regardless of whether state or federal law applied holding that an officer making a traffic stop may order passengers to exit the car pending completion of the stop holding that state court with jurisdiction over  301 claim should have applied federal labor law rather than state contract law holding that ejxcept in matters governed by the federal constitution or by acts of congress the law to be applied in any case is the law of the state holding that the plaintiffs state law claims are preempted by federal law