Case5:15-xr-90304-HRL Document30 Filed07/29/15 Page11 of 46 1 the Public Defender responded separately with filings on June 29, 2015. See Larsen Decl.; ECF 2 No. 29-1, Declaration of Assistant U.S. Attorney Jeff Schenk (“Schenk Decl.”). 3 II. 4 The Court reviews de novo a magistrate judge’s legal conclusions and reviews any 5 underlying factual findings for clear error. See Quinn v. Robinson, 783 F.2d 776, 811-12 (9th Cir. 6 1986); accord United States v. McDermott, 589 F. App’x 394, 395 (9th Cir. 2015). As Judge 7 Lloyd’s conclusion that the government must secure a search warrant on a showing of probable 8 cause in order to obtain historical CSLI is a legal determination, this Court reviews that 9 determination de novo. 10 11 United States District Court Northern District of California LEGAL STANDARD III. DISCUSSION A. Fourth Amendment Principles 12 The Fourth Amendment guarantees “[t]he right of the people to be secure in their persons, 13 houses, papers, and effects, against unreasonable searches and seizures.” U.S. Const. amend. IV. 14 Cell phones plainly qualify as “effects” under the meaning of the Fourth Amendment. See Oliver 15 v. United States, 466 U.S. 170, 177 n.7 (1984) (“The Framers would have understood the term 16 ‘effects’ to be limited to personal, rather than real, property.”). Further, as the text makes clear, 17 “the ultimate touchstone of the Fourth Amendment is ‘reasonableness.’” Riley v. California, 134 18 S. Ct. 2473, 2482 (2014) (quoting Brigham City v. Stuart, 547 U.S. 398, 403 (2006)). “Where,” as 19 here, “a search is undertaken by law enforcement officials to discover evidence of criminal 20 wrongdoing, reasonableness generally requires the obtaining of a judicial warrant.” Id. (brackets 21 omitted) (quoting Vernonia Sch. Dist. 47J v. Acton, 515 U.S. 646, 653 (1995)). The Fourth 22 Amendment’s warrant requirement “ensures that the inferences to support a search are ‘drawn by a 23 neutral and detached magistrate instead of being judged by the officer engaged in the often 24 competitive enterprise of ferreting out crime.’” Id. (quoting Johnson v. United States, 333 U.S. 25 10, 14 (1948). “In the absence of a warrant,” the U.S. Supreme Court has held, “a search is 26 reasonable only if it falls within a specific exception to the warrant requirement.” Id. 27 28 11 Case No. 15-XR-90304-HRL-1(LHK) ORDER AFFIRMING DENIAL OF APPLICATION FOR HISTORICAL CELL SITE LOCATION INFORMATION