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16
RILEY v. CALIFORNIA

Opinion of the Court

ing and an inspection of the cigarette pack found in his pocket constituted only minor additional intrusions compared to the substantial government authority exercised in taking Robinson into custody. See Chadwick, 433 U. S., at 16, n. 10 (searches of a person are justified in part by "reduced expectations of privacy caused by the arrest").

The fact that an arrestee has diminished privacy interests does not mean that the Fourth Amendment falls out of the picture entirely. Not every search "is acceptable solely because a person is in custody." Maryland v. King, 569 U. S. ____ , ____ (2013) (slip op., at 26). To the contrary, when "privacy-related concerns are weighty enough" a "search may require a warrant, notwithstanding the diminished expectations of privacy of the arrestee." Ibid. One such example, of course, is Chimel. Chimel refused to "characteriz[e] the invasion of privacy that results from a top-to-bottom search of a man's house as 'minor.'" 395 U. S., at 766-767, n. 12. Because a search of the arrestee's entire house was a substantial invasion beyond the arrest itself, the Court concluded that a warrant was required.

Robinson is the only decision from this Court applying Chimel to a search of the contents of an item found on an arrestee's person. In an earlier case, this Court had approved a search of a zipper bag carried by an arrestee, but the Court analyzed only the validity of the arrest itself. See Draper v. United States, 358 U. S. 307, 310-311 (1959). Lower courts applying Robinson and Chimel however, have approved searches of a variety of personal items carried by an arrestee. See, e.g., United States v. Carrion, 809 F. 2d 1120, 1123, 1128 (CA5 1987) (billfold and address book); United States v. Watson, 669 F. 2d 1374, 1383-1384 (CAll 1982) (wallet); United States v. Lee, 501 F. 2d 890, 892 (CADC 1974) (purse).

The United States asserts that a search of all data stored on a cell phone is "materially indistinguishable" from searches of these sorts of physical items. Brief for