Police hoping to rummage through a suspect’s cell phone after an arrest must apply for a warrant, the Ohio Supreme Court has ruled. That apparently makes it the first court to address a question I first wrote about two years ago, after Adam Gershowitz broached it in a law review article.


Normally, when police arrest someone—and recall that even trivial offenses may provide formal grounds for arrest—they’re entitled to conduct an incidental search of the person and their immediate vicinity, nominally for the purpose of uncovering any weapons and preventing the destruction of contraband. The new wrinkle as Gershowitz noted, is that we’ve begun routinely carrying vast stores of personal data around with us in our pockets: photos, correspondence, music and movies, Internet browsing histories, even whole libraries of books. What’s more, these little archives are typically connected, sometimes automatically, to still more personal information held remotely: mailboxes, calendars, bank accounts, purchasing histories, or in principle just about anything accessible online.


Suddenly a narrow, reasonable-sounding exception to the ordinary Fourth Amendment warrant requirement starts looking like a pretty huge loophole. The quantity of personal “papers and effects” that can be stored in an ordinary phone would have filled a house just a few decades ago. But if those smartphones are subject to “search incident to arrest,” there’s no longer any need to bother with judicial authorization for the search of a private home. And since a legal system governed by precedent subjects digital technologies to the tyranny of bad metaphors, there’s a disarmingly strong argument to be made that smartphones should be treated like any other physical “closed container”—a digital backpack or purse, at least with respect to the data stored locally on the phone.


This case involved more conventionally phone-like information: calling records. But the Court nevertheless saw the danger inherent in treating portable data storage devices as mere “containers,” holding that searches of phones were reasonable only to the extent they could be linked to the twin justifications of safety and preventing destruction of evidence. But as the ruling and dissent both note, there are a handful of precedents that appear to cut in the other direction. The question now is whether other courts will follow Ohio’s lead or remain mired in inapposite comparisons to knapsacks and cigarette packs.