What is the effect of obtaining the assistance and approval of a government attorney and a federal magistrate on an application for a search warrant?

Armed with this background knowledge, the agent took the affidavit to the United States Attorney's office before submitting it to the magistrate. Two attorneys reviewed the affidavit and made some changes to it. Following their approval, the agent then took the affidavit to the magistrate who also approved it. When neither the federal prosecutors nor the federal magistrate questioned him further on the contents of the affidavit, it was not unreasonable for the agent to subjectively assume that the warrant was valid. See United States v. Johns, 948 F.2d 599, 605 (9th Cir.1991), cert. denied, 112 S.Ct. 3046 (1992) (agents not required to disbelieve "experts"--a government attorney and a neutral detached magistrate). We conclude that possession of relevant background information, coupled with obtaining the assistance and approval of the United States attorneys and a neutral and detached magistrate, warrants application of the Leon good faith exception to the circumstances of this case.