federal test for its validitv incorporate state or tribal law. Becerra-Garcia was the subject of an investigatory traffic stop, the reasonableness of which depends only on reasonable suspicion, not on compliance with state or tribal law. See Haynie v. County of Los Angeles, 339 F.3d 1071, 1075 (9th Cir.2003) (investigatory stops require only reasonable suspicion). 4 . We acknowledge some inconsistency in our cases on this broad issue. See, e.g., Bingham v. City of Manhattan Beach, 341 F.3d 939, 950 (9th Cir.2003) (“in evaluating a custodial arrest executed by state officials, federal courts must determine the reasonableness of the arrest in reference to state law governing the arrest") (internal quotation marks omitted); Pierce v. Multnomah County, 76 F.3d 1032, 1041 (9th Cir. 1996) (<HOLDING>); Reed v. Hoy, 891 F.2d 1421, 1427 n. 5 (9th
holding that state law is immaterial for fourth amendment search analysis and refusing to suppress evidence obtained illegally under state law after warrantless arrest because the arrest rules that the officers violated were those of state law alone and as we have just concluded it is not the province of the fourth amendment to enforce state law that amendment does not require the exclusion of evidence obtained from a constitutionally permissible arrest holding in a  1983 case that city policy that authorized officers to detain people for nonarrestable offenses violated state law and therefore violated the fourth amendment holding that the fourth amendment protects people not places holding that arrest in backyard violated fourth amendment holding fourth amendment not violated by failure to announce where compliance would have increased officers peril