Singh v. Ilchert, 63 F.3d 1501, 1508 (9th Cir. 1995) ("A federal agency is obligated  to follow circuit precedent in cases originating within that circuit.")   There does not appear to be any case applying this doctrine to a case involving a consular post, but inasmuch as the consular post is an office of a federal agency, the Dep't of State, and the case originated in this circuit, with an I-130 or I-485 filed there, then the Singh v. Ilchert rule should apply. Thanks to Rick Coshnear.