Today, the Supreme Court unanimously invalidated warrantless searches of cell phones incident to arrest in Riley v. California and United States v. Wurie. Full disclosure: my colleagues and students with the Stanford Law School Supreme Court Litigation Clinic were counsel of record before the Court for Mr. Riley.
The opinion is exceedingly important, and not just because nowadays almost everyone carries a cell phone replete with personal photos, messages and other data. Indeed, the Court says that modern cell phones are now such a pervasive part of daily life “that the proverbial visitor from Mars might conclude they were an important feature of human anatomy”. The Court’s reasoning also will influence Fourth Amendment jurisprudence in fundamental privacy and surveillance cases going forward.
The most important takeaway from today’s opinion is that Digital Is Different. In support of the searches invalidated today, the government pushed the idea that searching an arrestee’s cell phone is no different than searching inside his pockets, or examining a cigarette pack found there, as the Court approved in United States v. Robinson, 414 U. S. 218 (1973). To the contrary, said the Court, “[t]hat is like saying a ride on horseback is materially indistinguishable from a flight to the moon.” Privacy advocates have long been saying that the volume and detail of digital information means that analogies to analogue world data should not control. The Supreme Court agrees.
What will this mean for the NSA’s bulk collection of call detail records and other so-called “metadata”? The Court expressly wants to preserve that question for another day. In a footnote, it says:
Because the United States and California agree that these cases involve searches incident to arrest, these cases do not implicate the question whether the collection or inspection of aggregated digital information amounts to a search under other circumstances.
Yet, the opinion suggests that when the Court has that question before it, the government’s approach may not win the day. So far, the government and the FISC have said that the 1979 case of Smith v. Maryland–approving warrantless installation of a “pen register” to capture numbers dialed–authorizes warrantless collection of metadata in general, and call detail records/Internet transactional data in particular. Similarly, the government depended on Smith in Riley and Wurie, arguing that a cell phone call log is just like the numbers dialed which a pen register captures. The Court says “No”. Specifically with regard to call detail records:
There is no dispute here that the officers engaged in a search of Wurie’s cell phone. Moreover, call logs typically contain more than just phone numbers; they include any identifying information that an individual might add, such as the label “my house” in Wurie’s case.
Given this reasoning, its not obvious that the simplistic NSA and the FISA Court legal justifications for bulk collection under either section 215 or the FISA pen register provisions are correct. I’ll be looking forward to whether the FISA Court’s next opinions authorizing bulk collection of call detail records under Section 215 discuss how Riley applies. [Further, today's Court opinion gives additional support to the recent Eleventh Circuit opinion in United States v. Davis rejecting warrantless location tracking via cell phone data.]
More generally, Digital is Different. The Court goes on at length about how the information stored on a cell phone is not analogous to the atoms which people generally carry with them:
Cell phones differ in both a quantitative and a qualitative sense from other objects that might be kept on an arrestee’s person. The term “cell phone” is itself misleading shorthand; many of these devices are in fact minicomputers that also happen to have the capacity to be used as a telephone. They could just as easily be called cameras, video players, rolodexes, calendars, tape recorders, libraries, diaries, albums, televisions, maps, or newspapers.
These qualitative and quantitative differences mean the Court will not blithely analogize modern technology to old possessions. Rather, it adopts a more categorical rule protecting digital devices generally, precisely to avoid such impossible line-drawing.
[A]n analogue test would launch courts on a difficult line-drawing expedition to determine which digi- tal files are comparable to physical records. Is an e-mail equivalent to a letter? Is a voicemail equivalent to a phone message slip? It is not clear how officers could make these kinds of decisions before conducting a search, or how courts would apply the proposed rule after the fact.
A second important takeaway is that the full Court appears open to the “mosaic theory” or something like it. The five concurring Justices in United States v. Jones (2012) sketched the outlines of a “mosaic theory” of Fourth Amendment protection, in holding that long term GPS installation and tracking requires a search warrant. While a particular piece of information may not be protected by the Fourth Amendment, government collection of information over time and in aggregate could violate the Fourth Amendment if it reveals to investigators something categorically more invasive about the suspect. As Justice Alito wrote, society might anticipate short term location tracking similar to that which officers would undertake in person, but that long term surveillance of 28 days such as that which occurred in Jones “surely” violated the expectation of privacy. The Riley opinion shows the full Court, and not just the five concurring Justices in Jones, are animated by similar “mosaic” considerations:
First, a cell phone collects in one place many distinct types of information—an address, a note, a prescription, a bank statement, a video— that reveal much more in combination than any isolated record. (emphasis added)
Third, the Court rejects the idea that voluntarily adopted Executive Branch or state police search protocols can insulate an investigative technique from the Fourth Amendment warrant requirement. Of course, cell phone searches incident to arrest could give police officers the ability to also search remotely stored files. The government conceded that this would take the search incident to arrest doctrine too far, and the Court agreed.
Such a search would be like finding a key in a suspect’s pocket and arguing that it allowed law enforcement to unlock and search a house.
In an effort to save warrantless local searches of the device, the government suggested that law enforcement agencies “develop protocols to address” concerns raised by cloud computing. The Court utterly rejected the idea that mere protocols were a substitute for advance judicial authorization via the warrant procedure.
Probably a good idea, but the Founders did not fight a revolution to gain the right to government agency protocols.
This raises the question of whether bulk collection or mass surveillance can meet Fourth Amendment requirements based merely on the Executive Branch’s adoption of post-collection minimization procedures or other privacy-enhancing agency practices and protocols. Foreign intelligence surveillance approvals regularly rely on the existence of minimization procedures to address the privacy interests of U.S. persons adversely affected. Yet, judicial review of minimization procedures is curtailed under section 702 of the FISA Amendments Act. What procedures there are fail to protect U.S. person data from being secretly used in criminal contexts. Nor do the procedures effectively protect constitutionally protected or traditionally private materials–like privileged communications with our attorneys–from government access and use.
In sum, Riley will be an incredibly important case moving forward, as courts parse the way new surveillance tools impact privacy in the Age of Snowden.
Two last points. First, congratulations to Professor Orin Kerr, whose thoughtful work in this area was cited not once, but twice, by the Court. Second, the trial lawyer in me can’t help but notice how important a factual record is. There were two points in Riley where the Court rejected a government justification for the search for lack of evidence. The Court said that cell phone searches incident to arrest could not be justified on the grounds of avoiding remote wiping or encryption.
We have also been given little reason to believe that either problem is prevalent.
Further, the Court was unswayed by the argument that cell phone searches were useful for 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 California offers evidence to suggest that their concerns are based on actual experience.
For more interesting thoughts on today’s grand development:
Orin Kerr: The significance of Riley