Peter A. Crusco

On Nov. 29, 2017, the U.S. Supreme Court heard oral argument in a significant privacy case implicating the Fourth Amendment interpretation in the digital age, Carpenter v. United States.1 At issue was whether certain telephone business records evidence, known as historical cell site location information (CSLI), was erroneously admitted at trial in violation of the Fourth Amendment to the U.S. Constitution prohibiting unreasonable searches and seizures. The CSLI records concerned a 127-day period, the alleged time period of the crimes charged, and were obtained by authorities without a search warrant satisfying the required standard of probable cause. The evidence was presented at petitioner Timothy Carpenter’s trial, and explained by an FBI expert and supported by accomplice testimony resulting in his conviction and lengthy prison sentence. Although not mentioned by name during the oral argument, the spirit of People v. Weaver, 12 N.Y.3d 433, a case decided by the New York Court of Appeals in 2009, dealing with the suppression of evidence resulting from the 65-day warrantless use by police of a GPS tracking device, had clearly descended over the courtroom. A Weaver mist like the presence of a Charles Dickens’ Christmas ghost seemed to be ever present, and barely visible in certain of the questions and expressed concerns by the learned justices. This article will analyze the issues raised in Carpenter, and compare them with those in Weaver, and in the spirit of the season, hope to shed new light on this evolving and often confusing area of privacy, third-party digital records and Fourth Amendment jurisprudence.

‘Weaver’: Warrantless GPS Tracking by Police

Weaver involved a burglary investigation in which the police, without a warrant, utilized a GPS tracking device on defendant’s van monitoring its movement for 65 days, resulting in defendant being charged with two burglaries. During that time the police constantly monitored the whereabouts of the vehicle. The New York State Court of Appeals, in a 4-3 opinion, authored by then Chief Judge Jonathan Lippman determined that this nonstop surveillance was not a mere enhancement of human sensory capacity, finding that the residual privacy expectation that defendant retained in his vehicle, while small, was adequate to support his claim of a violation of his New York Constitutional right protected by art. I. §12 to be free from unreasonable searches and seizures.

Writing for the majority, Judge Lippman included a reference to Justice Louis Brandeis’ dissent in Olmstead v. United States, 277 U.S. 438 (1928). There, Justice Brandeis offered an alternative interpretation of the Fourth Amendment broadly construing the protections of the Amendment sought by the makers of our Constitution to include evidence obtained from a warrantless wiretap, that is, not only the protection of a person’s property but to secure conditions favorable to the pursuit of happiness, recognizing: “the significance of man’s spiritual nature, of his feelings and of his intellect … [t]hey conferred, as against the Government, the right to be let alone—the most comprehensive of rights and the right most valued by civilized men. To protect that right, every unjustifiable intrusion by the Government upon the privacy of the individual, whatever the means employed, in a criminal proceeding, of facts ascertained by such intrusion must be deemed a violation of the Fourth Amendment.” Weaver, 438-39.

Until the decision in Katz v. United States, 389 U.S. 347, 357 (1967), Olmstead was the law of the land. Katz replaced the doctrinal property underpinnings, of the trespass doctrine of Olmstead with the protective ambit now understood to depend upon whether the individual asserting a protected interest had demonstrated a subjective expectation of privacy and whether that expectation would be accepted as reasonable by society. Katz, 389 U.S. at 361 (Harlan, J., concurring).

In distinguishing the beeper technology used in United States v. Knotts, 460 U.S. 276 (1983), the court in Weaver determined that the GPS technology used in Weaver was a “vastly different and exponentially more sophisticated and powerful technology that is easily and cheaply deployed and has virtually unlimited and remarkably precise tracking capability.” Weaver, 12 N.Y.3d at 441. This same argument was made by the petitioner in Carpenter but with respect to CSLI. The Weaver court explained that “GPS is not a mere enhancement of human sensory capacity, it facilitates a new technological perception of the world in which the situation of any object may be followed and exhaustively recorded over, in most cases, a practically unlimited period.” Thus, the court determined “[t]hat such a surrogate technological deployment is not—particularly when placed at the unsupervised discretion of agents of the state engaged in the often competitive enterprise of ferreting our crime—compatible with any reasonable notion of personal privacy or ordered liberty, would appear to us obvious.” Weaver, 12 N.Y.3d at 441. Justice Lippman further discounted Knotts’ finding that “[t]he science at issue in Knotts was, as noted, quite modest, amounting to no more than an incremental improvement over following a car by the unassisted eye.” Weaver, 12 N.Y.3d at 442.

The Weaver court found that the “massive invasion of privacy entailed by the prolonged use of the GPS device was inconsistent with even the slightest reasonable expectation of privacy.” Weaver, 12 N.Y.3d at 444. The court determined that defendant had a reasonable expectation of privacy that was infringed upon by the state’s placement and monitoring of the GPS device on his van to track his movements over a period of over two months, that there was a search under the New York State Constitution and that search was illegal because it was executed without a warrant, and without justification under any exception to the warrant requirement. The court also determined that in light of unsettled federal law on the issue, it premised its ruling on the New York Constitution alone. Weaver, 12 N.Y.3d at 445. Eight years later, the spirit of Weaver could be discerned during the oral argument before the U.S. Supreme Court in Carpenter v. United States.

‘Carpenter’: CSLI and Third-Party Business Records

Petitioner Carpenter was sentenced to a lengthy period of incarceration for his role in a series of armed robberies in 2010 and 2011 occurring in Indiana and Michigan. During his trial, Carpenter’s cell phone records, including tower information (CSLI), were admitted into evidence by the government, which when explained by an F.B.I. expert witness equipped with cell tower charts and maps, and in the context of the testimony by several of Carpenter’s accomplices, linked Carpenter’s cell phone with cell towers in the vicinity of the robberies he was charged with committing. This evidence was obtained by the government without a search warrant. Instead, the government utilized the mechanism under the Stored Communications Act, “SCA” which permits access to such records via a court order issued per §2703(d) of the SCA under a much lesser showing than probable cause. The 2703(d) order only requires a demonstration of “specific and articulable facts showing that there are reasonable grounds to believe that … the records or other information sought, are relevant and material to an ongoing criminal investigation.”

At a pre-trial suppression hearing, Carpenter challenged the admissibility of the historical cell site records evidence. He contended that the government was barred from using those records by his expectation of privacy in them and the government’s failure to obtain a probable cause-based warrant. Nevertheless, the hearing court found that the records fell into the “third-party doctrine,” that is, records shared with a third party are not protected by the Fourth Amendment, and therefore no expectation of privacy of the petitioner’s was violated. The U.S. Court of Appeals for the Sixth Circuit, United States v. Carpenter, 819 F.3d 880 (6th Cir. 2016) also rejected his arguments on the same grounds.

‘Carpenter’: Oral Argument

At oral argument before the U.S. Supreme Court, petitioner Carpenter made several arguments reminiscent of those made by Weaver in support of his position that the records should have been suppressed. First, that the accuracy of cell site location information continues to improve and makes it similar to the vehicle GPS data that the court found unacceptable in United State v. Jones2 as it may reveal a person’s detailed movements (T15, 28-29); second, that owning a cellular telephone is not a voluntary decision to disclose one’ s CSLI, because these devices have become indispensable for full participation in life (T16); and that the third-party doctrine should be modified as this type of data is far more sensitive than the financial records evidence involved in United States v. Miller, 425 U.S. 435, 442-44 (1976) and the telephone numbers dialed evidence in Smith v. Maryland, 442 U.S. 735, 742-45 (1979) (T15). Furthermore, that applying the third-party doctrine to all digital records held by third parties, given the technological advancements, would place all electronic communications accomplished through service providers, including emails, outside the scope of the Fourth Amendment protection. (T22).

The government asserted the third-party doctrine, contending that Carpenter could have no reasonable expectation of privacy in information that he voluntarily disclosed to a third party as per Miller and Smith. (T41, 80-81). Further, the government contended that although the technological issue in Carpenter admissibility of CSLI evidence may be new, the legal principles implicated by the case were not, and controlled by Miller and Smith. Further, the government relied upon the manner in which the government obtained the information, emphasizing that the cell phone providers created the records for their own purposes, and turned the records over to the government in response to a §2703(d) court order; the government did not collect the data itself.

Moreover, the government disputed Carpenter’s claims regarding the accuracy and therefore the intrusiveness of CSLI responding that CSLI information only placed Carpenter within a geographic sector that contained approximately 1,000 buildings and that this information alone did not allow it to place Carpenter at the scene of the crime. The government emphasized that the case involved acquiring cell site information from a business which is less accurate than that acquired from a cell phone’s GPS technology. (T44). Moreover, the government contended that the application of the third party doctrine does not depend on the level of sensitivity of the information disclosed or the limitation of use.

Justice Elena Kagan referenced the court’s prior decision in United States v. Jones, 132 S. Ct. 945 (2012) involving the employment of similar GPS tracking technology used in Weaver on a defendant’s car. In Jones, the Supreme Court ruled that attaching a GPS device to the car of a suspected drug dealer and using it to track the car’s movements constituted a “search” for purposes of the Fourth Amendment.

This was the same position taken by the New York Court of Appeals three years before Jones in Weaver. Justice Kagan questioned the government about how the Carpenter case differed from Jones and quoted Justice Samuel Alito’s opinion stating, “[s]ociety’s expectation has been that law enforcement and others would not, and indeed in the main simply cannot, monitor and catalogue every single movement of an individual’s … for a long period.” The government responded that there was a fundamental difference, because Carpenter involved “acquiring the business records of a provider which has determined to keep these records of the cell site information.” (T46). Justice Kagan remarked of the “obvious similarity” between Jones and Carpenter

in that in both cases there was reliance on a new technology that allows for 24/7 tracking. (T47). Different means but the same question as to the intrusion on a person’s expectation of privacy, “of who would be watching them when.” (T47). The government responded that people consent to these records being kept because they know that the calls they make require that the numbers be routed through a cell phone. (T48).

Justice Kagan explained that the records in Carpenter allowed for greater intrusion than the GPS placed on the car in Jones, because the surveillance of Jones was limited to where he went in his car but the surveillance in Carpenter, although done by a third-party business, was not so limited and had no boundaries. (T70). Justice Kagan further explained that, “Jones was just about a car; this is about every place that you are, whether you’re in a car or not.” She continued, referring to the government’s advocate, “[b]ut I recall that when you were here in the Jones case, your theory for why that was permissible was essentially that you had given that information to the entire public; in other words, just by being in the world, everybody sees you, everybody watches you, and you’ve lost your expectation of privacy in that way.”

Justice Stephen Breyer, though, commented that the information in this case was different as it was “highly personal information … closer to the diagnostic testing than it is to purely commercial information” (T77). Echoes of Chief Judge Lippman’s concerns in Weaver, are apparent, specifically, when he referred to the ability of GPS technology there that, “[d]isclosed in the data retrieved from the transmitting unit, nearly instantaneously with the press of a button on the highly portable receiving unit, will be trips the indisputably private nature of which takes little imagination to conjure …” Weaver, 12 N.Y.3d at 441.

The government posited that even if the court deems the government’s access to historical CSLI was a search, Congress properly calibrated the balancing of interests by requiring the government through a detached magistrate obtain a 2703(d) order to obtain the records, which was satisfied in Carpenter. (T85)


Critical to the Weaver decision was the New York Court of Appeal’s determination that there had been an infringement of the defendant’s reasonable expectation of privacy in the warrantless GPS monitoring by police of his van for 65 days and in the absence of exigent circumstances. This same inquiry concerning whether Carpenter had a reasonable expectation of privacy in historical CSLI held by third-party cellular companies is being assessed by the Justices of the U.S. Supreme Court in Carpenter. It was clear during oral argument in Carpenter that the same concerns expressed in the Weaver decision about ease of access by law enforcement to highly sensitive personal data of individuals, among other issues, was upper most in the minds of several of the Justices. Perhaps, Justice Breyer said it best when he commented “… [t]his is an open box. We know not where we go.” (T35). In the final assessment, what effect these Weaver-like concerns will have on the court in Carpenter will have to wait for the issuance of the Supreme Court’s decision. All we can do for now is stay tuned.


1. Where appropriate, page references to the oral argument in Carpenter v. United States, Docket No. 16-402, are indicated by “T” followed by the page number. The oral argument may be accessed at

2. In United States v. Jones, 565 U.S. 400, 417 (2012), Justice Sotomayor, in a concurring opinion, suggested that the third-party doctrine may have to be reconsidered: “[m]ore fundamentally, it may be necessary to reconsider the premise that an individual has no reasonable expectation of privacy in information voluntarily disclosed to third parties.”

Peter A. Crusco is executive assistant district attorney, Investigations division, Office of the Queens County District Attorney. The views expressed herein are the author’s, and do not necessarily reflect the policies or views of the office.