Carpenter v. United States

138 S.Ct. 2206

201 L.Ed.2d 507

Timothy Ivory CARPENTER, Petitioner

v.United States.

No. 16–402.

Supreme Court of the United States

Argued Nov. 29, 2017.

Decided June 22, 2018.

Nathan Freed Wessler, Ben Wizner, Brett Max Kaufman, American Civil Liberties, Union Foundation, New York, NY, David D. Cole, American Civil Liberties, Union Foundation, Washington, DC, Cecillia D. Wang, Jennifer Stisa Granick, American Civil Liberties, Union Foundation, San Francisco, CA, Harold Gurewitz, Gurewitz & Raben, PLC, Detroit, MI, Daniel S. Korobkin, Michael J. Steinberg, Kary L. Moss, American Civil Liberties, Union Fund of Michigan, Detroit, MI, Jeffrey L. Fisher, Stanford Law School, Supreme Court Litigation Clinic, Stanford, CA, for Petitioner.

Noel J. Francisco, Solicitor General, Kenneth A. Blanco, Acting Assistant Attorney General, Michael R. Dreeben, Deputy Solicitor General, Elizabeth B. Prelogar, Assistant to the Solicitor General, Jenny C. Ellickson, Attorney, Department of Justice, Washington, DC, for Respondent.

Chief Justice ROBERTS delivered the opinion of the Court.

This case presents the question whether the Government conducts a search under the Fourth Amendment when it accesses historical cell phone records that provide a comprehensive chronicle of the user's past movements.

I

A

There are 396 million cell phone service accounts in the United States—for a Nation of 326 million people. Cell phones perform their wide and growing variety of functions by connecting to a set of radio antennas called "cell sites." Although cell sites are usually mounted on a tower, they can also be found on light posts, flagpoles, church steeples, or the sides of buildings. Cell sites typically have several directional antennas that divide the covered area into sectors.

Cell phones continuously scan their environment looking for the best signal, which generally comes from the closest cell site. Most modern devices, such as smartphones, tap into the wireless network several times a minute whenever their signal is on, even if the owner is not using one of the phone's features. Each time the phone connects to a cell site, it generates a time-stamped record known as cell-site location information (CSLI). The precision of this information depends on the size of the geographic area covered by the cell site. The greater the concentration of cell sites, the smaller the coverage area. As data usage from cell phones has increased, wireless carriers have installed more cell sites to handle the traffic. That has led to increasingly compact coverage areas, especially in urban areas.

Wireless carriers collect and store CSLI for their own business purposes, including finding weak spots in their network and applying "roaming" charges when another carrier routes data through their cell sites. In addition, wireless carriers often sell aggregated location records to data brokers, without individual identifying information of the sort at issue here. While carriers have long retained CSLI for the start and end of incoming calls, in recent years phone companies have also collected location information from the transmission of text messages and routine data connections. Accordingly, modern cell phones generate increasingly vast amounts of increasingly precise CSLI.

B

In 2011, police officers arrested four men suspected of robbing a series of Radio Shack and (ironically enough) T–Mobile stores in Detroit. One of the men confessed that, over the previous four months, the group (along with a rotating cast of getaway drivers and lookouts) had robbed nine different stores in Michigan and Ohio. The suspect identified 15 accomplices who had participated in the heists and gave the FBI some of their cell phone numbers; the FBI then reviewed his call records to identify additional numbers that he had called around the time of the robberies.

Based on that information, the prosecutors applied for court orders under the Stored Communications Act to obtain cell phone records for petitioner Timothy Carpenter and several other suspects. That statute, as amended in 1994, permits the Government to compel the disclosure of certain telecommunications records when it "offers specific and articulable facts showing that there are reasonable grounds to believe" that the records sought "are relevant and material to an ongoing criminal investigation." 18 U.S.C. § 2703(d). Federal Magistrate Judges issued two orders directing Carpenter's wireless carriers—MetroPCS and Sprint—to disclose "cell/site sector [information] for [Carpenter's] telephone[ ] at call origination and at call termination for incoming and outgoing calls" during the four-month period when the string of robberies occurred. App. to Pet. for Cert. 60a, 72a. The first order sought 152 days of cell-site records from MetroPCS, which produced records spanning 127 days. The second order requested seven days of CSLI from Sprint, which produced two days of records covering the period when Carpenter's phone was "roaming" in northeastern Ohio. Altogether the Government obtained 12,898 location points cataloging Carpenter's movements—an average of 101 data points per day.

Carpenter was charged with six counts of robbery and an additional six counts of carrying a firearm during a federal crime of violence. See 18 U.S.C. §§ 924(c), 1951(a). Prior to trial, Carpenter moved to suppress the cell-site data provided by the wireless carriers. He argued that the Government's seizure of the records violated the Fourth Amendment because they had been obtained without a warrant supported by probable cause. The District Court denied the motion. App. to Pet. for Cert. 38a–39a.

At trial, seven of Carpenter's confederates pegged him as the leader of the operation. In addition, FBI agent Christopher Hess offered expert testimony about the cell-site data. Hess explained that each time a cell phone taps into the wireless network, the carrier logs a time-stamped record of the cell site and particular sector that were used. With this information, Hess produced maps that placed Carpenter's phone near four of the charged robberies. In the Government's view, the location records clinched the case: They confirmed that Carpenter was "right where the ... robbery was at the exact time of the robbery." App. 131 (closing argument). Carpenter was convicted on all but one of the firearm counts and sentenced to more than 100 years in prison.

The Court of Appeals for the Sixth Circuit affirmed. 819 F.3d 880 (2016). The court held that Carpenter lacked a reasonable expectation of privacy in the location information collected by the FBI because he had shared that information with his wireless carriers. Given that cell phone users voluntarily convey cell-site data to their carriers as "a means of establishing communication," the court concluded that the resulting business records are not entitled to Fourth Amendment protection. Id., at 888 (quoting Smith v. Maryland, 442 U.S. 735, 741, 99 S.Ct. 2577, 61 L.Ed.2d 220 (1979) ).

We granted certiorari. 582 U.S. ––––, 137 S.Ct. 2211, 198 L.Ed.2d 657 (2017).

II

A

The Fourth Amendment protects "[t]he right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures." The "basic purpose of this Amendment," our cases have recognized, "is to safeguard the privacy and security of individuals against arbitrary invasions by governmental officials." Camara v. Municipal Court of City and County of San Francisco, 387 U.S. 523, 528, 87 S.Ct. 1727, 18 L.Ed.2d 930 (1967). The Founding generation crafted the Fourth Amendment as a "response to the reviled ‘general warrants' and ‘writs of assistance’ of the colonial era, which allowed British officers to rummage through homes in an unrestrained search for evidence of criminal activity." Riley v. California, 573 U.S. ––––, ––––, 134 S.Ct. 2473, 2494, 189 L.Ed.2d 430 (2014). In fact, as John Adams recalled, the patriot James Otis's 1761 speech condemning writs of assistance was "the first act of opposition to the arbitrary claims of Great Britain" and helped spark the Revolution itself. Id., at –––– – ––––, 134 S.Ct., at 2494 (quoting 10 Works of John Adams 248 (C. Adams ed. 1856)).

For much of our history, Fourth Amendment search doctrine was "tied to common-law trespass" and focused on whether the Government "obtains information by physically intruding on a constitutionally protected area." United States v. Jones, 565 U.S. 400, 405, 406, n. 3, 132 S.Ct. 945, 181 L.Ed.2d 911 (2012). More recently, the Court has recognized that "property rights are not the sole measure of Fourth Amendment violations." Soldal v. Cook County, 506 U.S. 56, 64, 113 S.Ct. 538, 121 L.Ed.2d 450 (1992). In Katz v. United States, 389 U.S. 347, 351, 88 S.Ct. 507, 19 L.Ed.2d 576 (1967), we established that "the Fourth Amendment protects people, not places," and expanded our conception of the Amendment to protect certain expectations of privacy as well. When an individual "seeks to preserve something as private," and his expectation of privacy is "one that society is prepared to recognize as reasonable," we have held that official intrusion into that private sphere generally qualifies as a search and requires a warrant supported by probable cause. Smith, 442 U.S., at 740, 99 S.Ct. 2577 (internal quotation marks and alterations omitted).

Although no single rubric definitively resolves which expectations of privacy are entitled to protection,¹ the analysis is informed by historical understandings "of what was deemed an unreasonable search and seizure when [the Fourth Amendment] was adopted." Carroll v. United States, 267 U.S. 132, 149, 45 S.Ct. 280, 69 L.Ed. 543 (1925). On this score, our cases have recognized some basic guideposts. First, that the Amendment seeks to secure "the privacies of life" against "arbitrary power." Boyd v. United States, 116 U.S. 616, 630, 6 S.Ct. 524, 29 L.Ed. 746 (1886). Second, and relatedly, that a central aim of the Framers was "to place obstacles...