United States v. Chavez, ___ F.3d ___, 2008 WL 2893057 (10th Cir. 2008)
Based on collective knowledge doctrine, state policeman, who had no probable cause, could legitimately stop and search Defendant’s vehicle at the direction of DEA agents who did have probable cause to stop and arrest Defendant. (The stop was what the Court of Appeals termed a putative headlight infraction). The Court of Appeals calls this “vertical” collective knowledge: one officer has probable cause info but does not communicate it all–just the conclusions justifying probable cause–to the second officer.