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Welcome! The Privacy and Information Protection Committee works within the Section of Civil Rights and Social Justice to deal with issues arising from advances in technology and how it affects privacy and information protection, the regulation of government and private industry and countless other topics. We welcome your involvement and suggestions for Committee programs and invite you to join us. For more information on the Committee's work, or to join the Committee, contact the Section office.

2017-2018 Committee Work Plan

Privacy in the Courts

When it comes to digital privacy rights, Justice Roberts keeps it simple.

Alan Butler, EPIC Senior Counsel, Chair, Privacy and Information Protection Committee, ABA Section on Civil Rights and Social Justice

The Court watchers who downloaded the highly anticipated decision in Carpenter v. United States this morning discovered five opinions that totaled 119 pages. While the page count may answer the question of why opinions have been so slow this term, the opinions also raised new questions about the future of the Fourth Amendment. As anticipated, Chief Justice Roberts made clear that the Fourth Amendment extends to searches of cell site location information. But four dissenting opinions signaled a disagreement among some of the Justices about how and where to draw the Fourth Amendment line. The question going forward will be how lower courts apply the majority opinion, what Congress does next, and what to do with more than 90 pages of dissenting opinions.

The Chief Justice’s majority opinion provides a clear and cogent analysis of the privacy interests implicated by mobile location records while reconciling two distinct lines of Fourth Amendment cases. The first are the cases about the tracking of individuals’ movements over time. These include Knotts (and Karo) in the 1980s, the so-called “beeper” cases, and United States v. Jones in 2011. Jones concerned the attachment of a GPS tracking device on the defendant’s vehicle. The Court found unanimous agreement in the conclusion that such tracking triggered Fourth Amendment protections, but the Justices disagreed as to reasoning. A majority, in an opinion by Justice Scalia, set out a property-based approach to the Fourth Amendment. A shadow majority, in a concurrence by Justice Alito and a concurrence by Justice Sotomayor, viewed such tracking as violating an individual’s reasonable expectation of privacy following the Katz decision. The second line of cases concerned the collection of records held by third parties: Smith v. Maryland and Miller v. United States. In those cases, the Court said that individual could not invoke the Fourth Amendment to prevent collection of their call records or bank records held by third parties.

The Court’s opinion in Carpenter charts a new way forward for applying the Fourth Amendment to collection of sensitive digital data. The central premise of Justice Roberts’ opinion is there is a fundamental difference between the records in Smith and Miller and the mobile location data in Carpenter. Mobile location data is equivalent to the GPS data that the Court found was protected in Jones. In fact, the Court found that “historical cell-site records present even greater privacy concerns than the GPS monitoring of a vehicle we considered in Jones.” This is because “[w]hile individuals regularly leave their vehicles, they compulsively carry cell phones with them all the time,” including “into private residences, doctor’s offices, political headquarters, and other potentially revealing locales.” In addition, the “retrospective quality of the data here gives police access to a category of information otherwise unknowable.” Accessing historical location data gives the Government the power to “travel back in time to retrace a person’s whereabouts, subject only to the retention policies of wireless carriers.” And this data is “logged for all 400 million devices in the United States—not just those belonging to persons who might happen to come under investigation.” Unlike the device in Jones “police need not even know in advance whether they want to follow a particular individual, or when.”

The Court also distinguished its earlier decisions in Smith and Miller. Those decisions turned on the “nature of the particular documents sought” and that records had been “voluntarily” conveyed to third parties. The Court held that location data provides a “chronicle of a person’s physical presence compiled every day, every moment, over several years” far beyond what was at issue in Smith and Miller. The Court also held that users do not voluntarily convey this information to third parties: “Apart from disconnecting the phone from the network, there is no way to avoid leaving behind a trail of location data.” As the Court noted, the Government was not merely “asking for a straightforward application of the third-party doctrine, but instead a significant extension of it to a distinct category of information.” The Court refused to extend the third-party doctrine to sensitive mobile location data. Like in his opinion for a unanimous Court in Riley v. California (the case about warrantless searches of cell phones incident to arrest), Chief Justice Roberts offers a simple answer to the Fourth Amendment question. If you want to search a cell phone or collect historical location data: Get A Warrant.

The four dissenting opinions disagreed with the majority but could not agree as to why. Justice Kennedy wrote that there is no reason to distinguish mobile data in 2018 from the telephone records and financial record the Court considered in the 1970s. Justice Thomas argued that the text of the Fourth Amendment—“their persons, papers, and effects”—required a rejection of the entire line of cases following from Katz and a strict application of the third-party doctrine. Justice Alito provided a long history of the law of compulsory process, arguing essentially that this conduct was outside the scope of the Fourth Amendment.

Justice Gorsuch wrote a dissent that could easily have been a concurrence. His real dispute was with the reasoning of the majority not with the outcome. Interestingly, he would have gone further than Justice Roberts and overturned Smith and Miller. He proceeds to ask a series of broad questions, albeit providing no broad answers. Justice Gorsuch is clear on one point, “no one believes that” our “most private documents” can be reviewed by police merely because they “now reside on third party servers.” In his view, “[t]here is another way.” He argues the Court should use property concepts such as bailments, mixed property interests, and positive law protections. Under this view, many records that are held in trust by third parties would be Constitutionally protected. Justice Gorsuch distanced himself from the other dissents and also took issue with Justice Alito’s view of the subpoena power. Indeed, the only reason he offers for not concurring in the judgment is that the Defendant in Carpenter “forfeited perhaps his most promising line of argument.”

So what does this all mean for the Fourth Amendment going forward? This decision is an inflection point, following a trend that began in Jones and Riley. The Supreme Court has now extended Fourth Amendment protection in three search cases involving new technology. And Justice Roberts, who wrote two of the opinions for the Court, has helped fashion a Fourth Amendment for the digital age. Cell phone data and mobile location data are now both protected. But lower courts must now decide whether those same protections extend to other types of data and other surveillance techniques. There will no doubt be many future cases raising these questions, but the Court’s opinion in Carpenter outlines a coherent approach to answering those questions. And if the Government prefers more certainty in the meantime, then it should support efforts to conduct a comprehensive reform of federal privacy laws.

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Modified by Alan Butler on September 10, 2018

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