The district court’s duty at a suppression hearing is not de novo review of probable cause – it’s whether there is substantial evidence to support the conclusion of the issuing magistrate that there was probable cause. United States v. Mohring, 2019 U.S. Dist. LEXIS 97664 (N.D. Iowa June 11, 2019):
It is not the place of this Court to determine whether the affidavit is supported by probable cause. “[A]fter-the-fact scrutiny by courts of the sufficiency of an affidavit should not take the form of de novo review. A magistrate’s determination of probable cause should be paid great deference by reviewing courts.” Illinois v. Gates, 462 U.S. 213, 236 (1983) (citation and internal quotation marks omitted). “In reviewing the issuance of a warrant, a district court need not make a de novo inquiry into the existence of probable cause, but rather should uphold the decision to issue the warrant so long as it is supported by ‘substantial evidence in the record.'” United States v. Hallam, 407 F.3d 942, 948 (8th Cir. 2005) (quoting Massachusetts v. Upton, 466 U.S. 727, 728 (1984) (per curiam)); see also United States v. Reivich, 793 F.2d 957, 959 (8th Cir. 1986) (“[T]he decision to issue the warrant is to be upheld if supported by substantial evidence in the record.”). Accordingly, the Court finds it unnecessary to adopt Judge Roberts’ conclusion that the warrant was supported by probable cause, and will instead examine whether there is substantial evidence in the record to support Judge Wegman’s probable-cause finding.