Opinion ID: 2572
Heading Depth: 3
Heading Rank: 1

Heading: Standards for Probable Cause

Text: The Fourth Amendment prohibits unreasonable searches and seizures, and requires that no warrants shall issue, but upon probable cause, supported by Oath. U.S. Const. amend. IV. The Supreme Court has explained that probable cause is a fluid conceptturning on the assessment of probabilities in particular factual contextsnot readily, or even usefully, reduced to a neat set of legal rules. Illinois v. Gates, 462 U.S. 213, 232, 103 S.Ct. 2317, 76 L.Ed.2d 527 (1983). The task of the issuing magistrate [or judge [6] ]is simply to make a practical, common-sense decision whether, given all the circumstances set forth in the affidavit before him, ... there is a fair probability that contraband or evidence of a crime will be found in a particular place. Id. at 238, 103 S.Ct. 2317. This Court must afford great deference to the district court's probable cause determination. Gates, 462 U.S. at 236, 103 S.Ct. 2317 (internal quotation marks omitted). Our duty on review, therefore, is simply to ensure that the [district court] had a substantial basis for... concluding that probable cause existed. Id. at 238, 103 S.Ct. 2317 (internal marks omitted). Nevertheless, under this standard, we may properly conclude that... [a] warrant was invalid because the [district court's] probable-cause determination reflected an improper analysis of the totality of circumstances. Leon, 468 U.S. at 915, 104 S.Ct. 3405 (citing Gates, 462 U.S. at 238-39, 103 S.Ct. 2317).