United States District Court Northern District of California Case5:15-xr-90304-HRL Document30 Filed07/29/15 Page17 of 46 1 in some instances CSLI could locate an individual within her home, Hr’g Tr. at 30:15-20, 31:16- 2 32:4, and did not dispute that CSLI will become more precise as the number of cell towers 3 continues to multiply, id. at 32:5-9. This admission is of constitutional significance because rules 4 adopted under the Fourth Amendment “must take account of more sophisticated systems that are 5 already in use or in development.” Kyllo, 533 U.S. at 36. 6 In fact, the information the government seeks here is arguably more invasive of an 7 individual’s expectation of privacy than the GPS device attached to the defendant’s car in Jones. 8 This is so for two reasons. First, as the government conceded at the hearing, over the course of 9 sixty days an individual will invariably enter constitutionally protected areas, such as private 10 residences. Hr’g Tr. at 18:15-24. Tracking a person’s movements inside the home matters for 11 Fourth Amendment purposes because “private residences are places in which the individual 12 normally expects privacy free of governmental intrusion not authorized by a warrant, and that 13 expectation is plainly one that society is prepared to recognize as justifiable.” Karo, 468 U.S. at 14 714; see also Kyllo, 533 U.S. at 31 (“At the very core of the Fourth Amendment stands the right of 15 a man to retreat into his own home and there be free from unreasonable governmental intrusion.” 16 (internal quotation marks omitted)). As one court put it, “Because cellular telephone users tend to 17 keep their phone on their person or very close by, placing a particular cellular telephone within a 18 home is essentially the corollary of locating the user within the home.” See In re Application of 19 U.S. for an Order Authorizing Disclosure of Location Info. of a Specified Wireless Tel., 849 F. 20 Supp. 2d 526, 541 (D. Md. 2011). 21 Second, the government conceded at oral argument that, compared to GPS tracking of a 22 car, the government will “get more information, more data points, on the cell phone” via historical 23 CSLI. Hr’g Tr. at 29:8-9; see also id. at 29:19-21 (“But, yes, of course the person has the phone 24 more than they have their car, most people at least do, so it gives [the government] more data.”). 25 Cell phones generate far more location data because, unlike the vehicle in Jones, cell phones 26 typically accompany the user wherever she goes. See Wessler Decl. ¶¶ 8-10 (describing a Sixth 27 28 17 Case No. 15-XR-90304-HRL-1(LHK) ORDER AFFIRMING DENIAL OF APPLICATION FOR HISTORICAL CELL SITE LOCATION INFORMATION