03/02/2020 Riley v. California, 134 S. Ct. 2473 - Supreme Court 2014 - Google Scholar A We first consider each Chimel concern in turn. In doing so, we do not overlook Robinson's admonition that searches of a person incident to arrest, "while based upon the need to disarm and to discover evidence," are reasonable regardless of "the probability in a particular arrest situation that weapons or evidence would in fact be found." 414 U.S., at 235, 94 S.Ct. 467. Rather than requiring the "case-by-case adjudication" that Robinson rejected, ibid., we ask instead whether application of the search incident to arrest doctrine to this particular category of effects would "untether the rule from the justifications underlying the Chimel exception," Gant, supra, at 343, 129 S.Ct. 1710. See also Knowles v. Iowa, 525 U.S. 113, 119, 119 S.Ct. 484, 142 L.Ed.2d 492 (1998) (declining to extend Robinson to the issuance of citations, "a situation where the concern for officer safety is not present to the same extent and the concern for destruction or loss of evidence is not present at all"). 1 Digital data stored on a cell phone cannot itself be used as a weapon to harm an arresting officer or to effectuate the arrestee's escape. Law enforcement officers remain free to examine the physical aspects of a phone to ensure that it will not be used as a weapon — say, to determine whether there is a razor blade hidden between the phone and its case. Once an officer has secured a phone and eliminated any potential physical threats, however, data on the phone can endanger no one. Perhaps the same might have been said of the cigarette pack seized from Robinson's pocket. Once an officer gained control of the pack, it was unlikely that Robinson could have accessed the pack's contents. But unknown physical objects may always pose risks, no matter how slight, during the tense atmosphere of a custodial arrest. The officer in Robinson testified that he could not identify the objects in the cigarette pack but knew they were not cigarettes. See 414 U.S., at 223, 236, n. 7, 94 S.Ct. 467. Given that, a further search was a reasonable protective measure. No such unknowns exist with respect to digital data. As the First Circuit explained, the officers who searched Wurie's cell phone "knew exactly what they would find therein: data. They also knew that the data could not harm them." 728 F.3d, at 10. The United States and California both suggest that a search of cell phone data might help ensure officer safety in more indirect ways, for example by alerting officers that confederates of the arrestee are headed to the scene. There is undoubtedly a strong government interest in warning officers about such possibilities, but neither the United States nor 2486 California offers evidence to suggest that their concerns are based on actual experience. The *2486 proposed consideration would also represent a broadening of Chimel's concern that an arrestee himself might grab a weapon and use it against an officer "to resist arrest or effect his escape." 395 U.S., at 763, 89 S.Ct. 2034. And any such threats from outside the arrest scene do not "lurk[] in all custodial arrests." Chadwick, 433 U.S., at 14-15, 97 S.Ct. 2476. Accordingly, the interest in protecting officer safety does not justify dispensing with the warrant requirement across the board. To the extent dangers to arresting officers may be implicated in a particular way in a particular case, they are better addressed through consideration of case-specific exceptions to the warrant requirement, such as the one for exigent circumstances. See, e.g., Warden, Md. Penitentiary v. Hayden, 387 U.S. 294, 298-299, 87 S.Ct. 1642, 18 L.Ed.2d 782 (1967) ("The Fourth Amendment does not require police officers to delay in the course of an investigation if to do so would gravely endanger their lives or the lives of others."). 2 The United States and California focus primarily on the second Chimel rationale: preventing the destruction of evidence. Both Riley and Wurie concede that officers could have seized and secured their cell phones to prevent destruction of evidence while seeking a warrant. See Brief for Petitioner in No. 13-132, p. 20; Brief for Respondent in No. 13-212, p. 41. That is a sensible concession. See Illinois v. McArthur, 531 U.S. 326, 331-333, 121 S.Ct. 946, 148 L.Ed.2d 838 (2001); Chadwick, supra, at 13, and n. 8, 97 S.Ct. 2476. And once law enforcement officers have secured a cell phone, there is no longer any risk that the arrestee himself will be able to delete incriminating data from the phone. The United States and California argue that information on a cell phone may nevertheless be vulnerable to two types of evidence destruction unique to digital data — remote wiping and data encryption. Remote wiping occurs when a phone, connected to a wireless network, receives a signal that erases stored data. This can happen when a third party sends a remote signal or when a phone is preprogrammed to delete data upon entering or leaving certain geographic areas (socalled "geofencing"). See Dept. of Commerce, National Institute of Standards and Technology, R. Ayers, S. Brothers, & W. Jansen, Guidelines on Mobile Device Forensics (Draft) 29, 31 (SP 800-101 Rev. 1, Sept. 2013) (hereinafter Ayers). https://scholar.google.com/scholar_case?case=9647156672357738355&q=riley+v.+california&hl=en&as_sdt=2006 5/13