Opinion of the Court
Although the Government recognizes the problem, its proposed solutions are unclear. It suggests that officers could disconnect a phone from the network before searching the device — the very solution whose feasibility it contested with respect to the threat of remote wiping. Compare Tr. of Oral Arg. in No. 13-132, at 50-51, with Tr. of Oral Arg. in No. 13-212, pp. 13-14. Alternatively, the Government proposes that law enforcement agencies "develop protocols to address" concerns raised by cloud computing. Reply Brief in No. 13— 212, pp. 14— 15. Probably a good idea, but the Founders did not fight a revolution to gain the right to government agency protocols. The possibility that a search might extend well beyond papers and effects in the physical proximity of an arrestee is yet another reason that the privacy interests here dwarf those in Robinson.
C
Apart from their arguments for a direct extension of Robinson, the United States and California offer various fallback options for permitting warrantless cell phone searches under certain circumstances. Each of the proposals is flawed and contravenes our general preference to provide clear guidance to law enforcement through categorical rules. "[I]f police are to have workable rules, the balancing of the competing interests . . . 'must in large part be done on a categorical basis — not in an ad hoc, case-by-case fashion by individual police officers.'" Michigan v. Summers, 452 U. S. 692, 705, n. 19 (1981) (quoting Dunaway V. New York, 442 U. S. 200, 219-220 (1979) (White, J., concurring)).
The United States first proposes that the Gant standard be imported from the vehicle context, allowing a warrantless search of an arrestee's cell phone whenever it is reasonable to believe that the phone contains evidence of the crime of arrest. But Gant relied on "circumstances unique
