United States v. Flores-Lopez, 670 F.3d 803

Police arrested Flores-Lopez and Santana-Cabrera for drug distribution after an informant overheard a drug sale plan involving Flores-Lopez; a cell phone was seized from Flores-Lopez and two from Santana-Cabrera’s truck.
Authorities searched Flores-Lopez’s phone for its number at the scene and sought three months of call history from the carrier; Flores-Lopez objected to the phone’s non-warrant search and the call-history evidence.
The government argued a cell phone is a container and may be searched incident to arrest under Robinson, with limited intrusion to obtain the number; the number would then permit lawful subpoena of call history.
The court recognizes a modern cell phone stores vast personal data and that this makes a blanket application of Robinson inappropriate for such devices.
The court ultimately limits the holding to a minimal search of the number itself, noting the possibility of remote wiping and the availability of protective measures, but declines a broader warrantless search of contents.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Is a cell phone search without a warrant permissible to obtain its phone number incident to arrest?	USA: phone is a container; number discovery is justified.	Flores-Lopez: no warrant means unreasonable search.	Yes, minimal search to obtain number permissible.
Is obtaining call history from the carrier admissible as fruit of a lawful number search?	USA: lawful number enables subpoena; history admissible.	Flores-Lopez: warrants still required for subsequent data.	Yes, call history lawful if number obtained lawfully.

New York v. Belton, 453 U.S. 454 (1981) (container concept for searches incident to arrest)
United States v. Robinson, 414 U.S. 218 (1973) (search incident to arrest—no weapon/contraband focus required)
United States v. Jones, 132 S. Ct. 945 (2012) (GPS device as a search; focus on property intrusion)