The legal landscape concerning U.S. law enforcement’s use of a range of differing developing technologies can best be characterized as a long and winding road. Unlike many nations that have codified comprehensive legal structures to address issues of personal privacy, the United States has an ad hoc system of privacy protection. The system varies based on subject matter areas, like financial and health care–related information, as well as on a state and local basis. This makes developing general guidelines for privacy guidance and protection difficult at best.
Given the absence of a comprehensive body of controlling authority on the issue, law enforcement professionals are left with looking to court decisions in the attempt to discern legal limits on technology usage and understand how to best govern the intersection of emerging technology and privacy protections. Unfortunately, this approach involves a piecemeal assessment. Moreover, technology procurement and deployment decisions are often required before there is definitive guidance. This temporal issue can result in the need for substantial procedural and policy overhauls as well as the overturning of criminal cases years down the road when a court reaches a final adjudication. As law enforcement officials struggle to navigate the use of emerging technology, they should be mindful of the limitations of a case-by-case approach and attempt to look at the trends evident in decisions. A good starting place is examining developments on the issue in the U.S. Supreme Court.
The continuing pace of technology development has proved almost as challenging for the courts as it has for law enforcement. This is a theme frequently echoed by the Supreme Court. Understanding the road that the Supreme Court has taken to reach some of its most recent decisions should provide some insights for law enforcement executives as they grapple with the application of emergent technology. This is particularly so for those technologies that involve digital-based surveillance and the application of supercomputing technology. As law enforcement agencies wrestle with use of advanced analytics and artificial intelligence applied to a growing collection of data sources, this is especially important. In 2018, the U.S. Supreme Court made some significant pronouncements with respect to technology and privacy. In the process, the court has limited or eliminated some long-standing investigative practices that law enforcement practitioners were previously able to employ. This was not a final pronouncement, but it stands as an important waypoint on an over 40-year journey.
Examining the case of Carpenter v United States, the concern of the court regarding law enforcement exploitation of digital information and processing technology is evident.1 The case involved law enforcement access to data from cellphone usage, which allowed for tracking the whereabouts of an individual over a wide geographic distance for an extended time period. The Supreme Court sought to protect persons from this practice of accessing the personal data of individuals and the monitoring of their whereabouts, which the court viewed as law enforcement overreach. In reaching its decision in Carpenter, the court demonstrated a willingness to strip away long-approved practices of law enforcement.
Understanding the Carpenter Decision
The U.S. Supreme Court’s decision in Carpenter is the product of an over 40-year debate about the existence of an informational privacy interest protected under the Fourth Amendment. In a 2011 decision involving government employee background checks, the Supreme Court majority observed,
In two cases decided more than 30 years ago, this Court referred broadly to a constitutional privacy “interest in avoiding disclosure of personal matters.”2
We assume, without deciding, that the Constitution protects a privacy right of the sort mentioned in Whalen and Nixon.3
The holding in Carpenter explicitly recognized the existence of a protected right to informational privacy. The decision should serve as a cautionary tale for current law enforcement operations with a range of other new technologies that can monitor individual movements. As an example, the application of video analytic tools like license plate or facial recognition, which can turn the growing number of video camera feeds available to government into both real-time and investigative tools to monitor the movement of individuals, may impinge on protected privacy rights.
In Carpenter, a five to four decision, the court held the Fourth Amendment was violated when the FBI secured a suspect’s cell location information from a cellphone provider through a court order issued pursuant to provisions of the Stored Communications Act, rather than through a warrant.4 The cell site location information (CSLI), obtained from the third-party cell providers allowed the FBI to track the location of the suspect’s cellphone over a lengthy period of time and match that information to a multi-state pattern of robberies The court concluded that, given individuals’ reasonable expectation of privacy in the CSLI of their cellphones, a search warrant was required. The decision not only represents adoption of new rule in assessing an individual’s privacy interests in data, it also serves to impose new requirements in the assessment of privacy interests in information held by third parties. The Carpenter case has important implications for government surveillance activities and the ability of government agents to access information held by third parties.
Writing for the majority of the court in Carpenter, Chief Justice John Roberts noted the prevalence of cellphone technology in the United States and the way in which those phones operate—continuously sending out radio signals looking for available cell sites so that voice communication and data transfers can occur. The record of those transmissions created the CSLI, which allowed for the plotting of the general location of a cellphone at specific times.5 While the CSLI is maintained and used by phone carriers for a wide range of commercial purposes, including billing and the assessment of roaming charges related to specific accounts, the court concluded that the nature of the location data gave an individual an important protectible privacy interest.
The Carpenter majority noted that one of the principal functions of the Fourth Amendment was to “safeguard the privacy and security of individuals from arbitrary invasion by government.”6 Discussing the evolution of Fourth Amendment jurisprudence from a purely property-based concept where trespass was required before a Fourth Amendment violation could be established, the court noted an alternative basis examining an individual’s subjective expectations of privacy that “society is prepared to accept as reasonable.”7 The court reasoned that the protection of privacy was critical in the face of technological innovation and observed that the central aim of the U.S. Constitution’s framers was “to place obstacles in the way of a too permeating police surveillance.”8
Against this general backdrop of Fourth Amendment analysis, the Carpenter court went on to examine the implications of government access to CSLI without a warrant. The court concluded that, because the CSLI data raised the possibility of tracking the whole of a person’s movements over an extended time, it gives rise to reasonable expectations of privacy. Thus, accessing that data constituted a search under the Fourth Amendment.
The conclusion that the government had conducted a search of property where the defendant had a reasonable expectation of privacy did not, however, end the analysis. The government argued that, even if there were a protectable privacy interest in the CSLI, the privacy interest was diminished or extinguished because it was possessed by a third party. The third-party exception to the requirement for a warrant was a well-established rule.9 The reasoning supporting the exception was twofold. First, the voluntary sharing of that information with a third party undercut the notion of an individual’s privacy interest in the information. Second, an individual’s action in surrendering the information to a third party constituted an acceptance of the risk that, despite agreed limitations on the use of such information placed in the hands of the third party, the information might still be turned over to the government.
The court rejected the argument that the third-party exception was controlling and that the CSLI—which was a business record of the phone company and not the property of the defendant—was subject to production in accordance with the compulsory process of a court order under the provisions of the Stored Communications Act. The court noted the significant societal shift that proliferation of cellphone communications had stimulated over recent years. It observed that for many persons, their cellphone was almost an appendage of their person—never more than a few feet away. The court further noted the detailed and encyclopedic nature of CSLI recordkeeping of information automatically and constantly transmitted from cellphones. The result of this information was the ability to detail movement of individuals over periods of months and even years. In a departure from the general focus of Supreme Court decisions based solely on the facts of a specific case, the majority even observed that the detail of CSLI records were continuing to advance since the inception of the case.
Carpenter and the Riley and Jones Decisions
The decision in Carpenter was significantly influenced by two other recent decisions of the U.S. Supreme Court addressing informational privacy—Riley v California and United States v. Jones.10 Both cases help put the rulings of Carpenter into a larger context and demonstrate the potentially expansive nature of the Carpenter decision.
The decision in Riley involved two consolidated cases—a California state prosecution and a federal prosecution. The cases shared a common question of “whether the police may, without a warrant, search digital information on a cell phone seized from an individual who has been arrested.”11 The subsequent holding identified a bright line rule for officers to follow. That rule resulted in stripping officers of the ability to search the contents of the phone absent a warrant.
The facts in the California case addressed in the Riley decision involved a traffic stop based on probable cause that concluded in Riley’s custodial arrest. An inventory search of his vehicle resulted in the recovery of two loaded handguns from under the hood. As part of a search incident to arrest of Riley a “smart phone” was recovered from his pants pocket.12 The cellphone was accessed by the officer on the scene and subsequently accessed at the station. Information, including photographs and videos found in the phone, indicated that Riley was a street gang member. The information evidencing street gang membership was adduced as an aggravating factor in Riley’s trial in connection with a prior shooting.
The federal case consolidated in Riley involved the search of a flip phone, which was one of two phones seized from Wurie when he was arrested for drug trafficking. The search of the flip phone occurred at the station where Wurie was taken into custody when the phone kept receiving calls. The officers accessed the phone’s call log and determined it was the number identified on the phone as “my house” that was calling the phone. The search also revealed a picture of a woman and child on the phone’s screen. Officers used the phone number they retrieved to find an address and proceeded to an apartment building where they found Wurie’s name on a mailbox. The officers were also able to identify a woman through a window in the apartment, who looked like the woman whose picture was found on Wurie’s phone. The officers obtained a warrant and discovered 215 grams of crack cocaine, drug paraphernalia, a weapon, and ammunition in the apartment.
The Riley decision in which eight of the nine justices joined and one concurred, provides law enforcement with clear guidance—cellphone searches generally require a warrant. The court observed succinctly that
[o]ur holding, of course, is not that the information on a cell phone is immune from search; it is instead that a warrant is generally required before such a search, even when a cell phone is seized incident to arrest.13
In reaching that holding, the court rejected application of what had been a long-accepted search doctrine allowing relatively unfettered discretion for officers to search through the possessions of an arrestee. The court concluded that the characteristics of pervasive smartphone (and even not-so-smart flip phone) usage and the expectations of privacy of the public carrying these devices, made the phones fundamentally different in kind and character than other items individuals might carry on their person. Those findings figured prominently in the majority’s opinion in Carpenter with respect to the assessment of the privacy interest. The court concluded that the expansive amounts of personal data contained on the devices created a heightened privacy interest for individuals.
A second case which proved significant to the majority opinion in Carpenter was the Jones case, decided by the court in 2012. However, it was the two concurring opinions in Jones (joined by a total of five justices) that was most influential to the majority in Carpenter. In Jones, the Supreme Court addressed the constitutionality of warrantless use of a GPS tracking device. In that case the FBI had installed a GPS tracking device after the expiration of a warrant that had been issued to install the tracker. The tracking device was operated 24 hours per day for a period of four weeks, tracking the location of the suspect’s vehicle. Based in part on the data from the tracking device, the suspect, Jones, was indicted and subsequently convicted of narcotics related conspiracy charges.
In affirming the reversal of Jones’s conviction, the Supreme Court majority found that the installation of the GPS device on his vehicle without a warrant constituted a Fourth Amendment violation. The four justices’ majority opinion (in which Justice Sotomayor concurred) was narrowly focused on the existence of a trespass to the vehicle. Accordingly, the collection of digital GPS surveillance data flowing from that trespass was a Fourth Amendment violation, requiring that evidence to be suppressed.
Both of the concurring opinions (one authored by Justice Alito with whom Justices Ginsburg, Breyer, and Kagan joined and the second authored by Justice Sotomayor) offered an alternative basis for suppressing the GPS evidence suggesting that the pervasive type of government surveillance without a warrant violated privacy rights protected by the Fourth Amendment.14 Justice Alito’s concurrence rejected trespass as the basis for the finding of a Fourth Amendment violation in the case. However, because the concurring opinion of Justice Sotomayor accepted the majority’s finding that trespass was a valid basis for establishing a Fourth Amendment violation, the final holding in Jones case was limited to that narrower basis. It is, however, the broader findings of the Alito and Sotomayor concurrences that the court expressly adopts in Carpenter.
Looking to the two concurring opinions of five justices in Jones, the court in Carpenter acknowledged the fact that technology developments in the fields of surveillance and tracking raise significant and legitimate privacy concerns. The amount of location data that can be acquired and processed by the government using modern technology raises the specter of persistent mass surveillance, inconsistent with Fourth Amendment protections. The Carpenter majority went on to conclude that, like the GPS data that raised concerns in Jones, the CSLI data raised similar possibilities of tracking the whole of a person’s movements such that the court concluded it gives rise to reasonable expectations of privacy. Thus, the Carpenter majority concluded that such practices in the absence of a warrant are generally prohibited.
Some Thoughts on a Path Forward
The Carpenter decision, as well as the decisions in Riley and the concurring opinions in Jones, do offer some guidance for law enforcement searching for a path forward. As agencies evaluate emerging technologies and consider implementation, the following concepts and lessons should be considered.
Understanding the Penalty for Miscalculation on Warrant Requirements Is Essential: It should not be lost on law enforcement professionals that, in the Carpenter, Riley, and Jones cases, criminal convictions were reversed because evidence was found to have been gathered in derogation of protected privacy rights. While in all the cases, warrants were available, law enforcement did not pursue warrants because they did not believe them to be necessary. In Jones, the warrant for the GPS tracking device was allowed to expire. In the Carpenter case, the statutory articulated process did not require a warrant, but the Supreme Court later concluded the Fourth Amendment did require one. The lesson here is that, even in an instance where it appears that a warrant in not required, if the prospect of seeking a warrant is available, it should be considered.
Concerns Over Emerging Technology May Alter Existing Investigative Tools: In addition to considering the prospect of losing individual convictions, law enforcement officials should keep in mind the supportive investigative tools that have been lost or impaired in conjunction with perceived law enforcement overreach through emerging technology use. So strongly has the U.S. Supreme Court felt about protecting the informational privacy of individuals that established investigative tools like search incident to arrest and the third-party exception to the warrant rule have been laid aside. Overturning those long-standing precedents demonstrates the strength of judicial concern.
Real-Time Use of Emerging Technology in Exigent Circumstance Is Likely Permissible: The Supreme Court’s opinions do recognize that, in exigent circumstances, the application of technology to locate some individuals is consistent with constitutional protections. Using location technology in circumstances like finding persons at large who may pose a danger to the community seems to find approval in these decisions. This should key in law enforcement officials to the fact that, in addition to the capabilities of the technology itself, the application or use-case of the technology is important. Court opinions seem to be more receptive to the use of technology for real-time observation rather than use for investigation of crimes that have occurred.
Data Minimization in Collection and Limited Use of Analytics Are Important Considerations: Law enforcement officials should note that Supreme Court decisions focus extensively on the amounts of data that are being collected and analyzed. The larger the data compilations, the greater the concern. Additionally, the advancements in ability to store, process, and analyze that data exacerbates that concern. Just as the court first noted in Whelan v. Roe, a large concentration of personal information under control of the government that the government can analyze through advanced technology is a concern.15 Consistent with those concerns, law enforcement should look to minimize the amounts of data it collects and analyze only those data which are necessary to accomplish defined law enforcement tasks.
Targeted Use of Data and Analytics Should Be a Focus: Analytic surveillance tools like facial recognition and license plate recognition, combined with a proliferation of public and private video, will certainly raise new court challenges and concerns. How law enforcement accesses the data it analyzes, the data sources utilized, the amount of data collected, and the tools used for analyzing that data, along with the circumstances of real-time or forensic investigative use, will be important factors in assessing privacy concerns. With respect to the use of compiled location data in long-term investigations like narcotics or crime pattern robberies, securing warrants would be advisable. Reliance on existing compulsory process tools may now prove to be misplaced. However, where a limited amount of data is being sought and time is of the essence, in cases like a kidnapping or where police are searching for an offender at large, compulsory process may still suffice.
Predicting the Future of Privacy Protection Requirements Remains Imprecise: While technology can threaten privacy, it can also serve to change the public’s privacy expectations. Certainly, the proliferation of cellphones with the capability of capturing and transmitting video images changes individuals’ expectations of privacy in their personal conduct in public. The courts recognize that privacy norms are shifting, just as they recognize that legislative entities rather than courts are better equipped for assessing and addressing privacy interests. However, in the absence of legislative action, courts remain the major source for balancing technology and privacy. Knowing where the dividing line is located will continue to be challenging for law enforcement.
Governance and Risk Management Can Minimize Risk: In the face of an unpredictable legal environment, strong governance and controls over emerging technologies may help to minimize risk. Tools like privacy assessments and written policy development should be considered and utilized in connection with the adoption of emerging technologies. Measures like seeking warrants where practicable and limiting data collection and application of analytics provide a path forward. For those agencies looking to adopt new technologies, the IACP Technology Policy Framework offers a thoughtful approach to assessing and implementing emerging technology.16 Moreover, as with all new tools adopted by law enforcement, continuing management oversight is critical.
Notes:
1 Carpenter v. United States, 585 U.S. ___, 2018; U.S. LEXIS 3844.
2 The court cited Whalen v. Roe, 429 U.S. 589, 599-600, (1977); Nixon v. Administrator of General Services, 433 U.S. 425, 457, 97 S. Ct. 2777, 53 L. Ed. 2d 867 (1977).
3 NASA v. Nelson, 562 U.S. 134, 138 (2011).
4 18 U.S.C.S. § 2703(d).
5 The accuracy of tracking is a function of the density of cell sites in a given area. The greater the density of cell sites, the more precise the location plotting. In urban areas the cell site locations are generally denser than what is found in rural areas, so location plotting based on CSLI is more precise in urban areas. With the advent of small-cell technology the number of cell sites will proliferate exponentially greatly enhancing both cell coverage and the ability to more precisely track location using CSLI.
6 Carpenter, 585 U.S. ___, citing Camara v. Municipal County Court of City and County of San Francisco, 387 U.S. 523, 528 (1967).
7 Carpenter, 585 U.S. ___, citing Katz v. United States, 389 U. S. 347, 351 (1967).
8 Carpenter, 585 U.S. ___, citing United States v. De Ri, 332 U.S. 581, 595 (1948).
9 In United States v. Miller, 425 U. S. 435 (1976), the court found that government acquisition of financial records like bank statements and cancelled checks did not require a warrant. Similarly, the court, in Smith v. Maryland, 442 U. S. 735 (1979), found that the government could obtain phone company records registering the incoming and outgoing calls without resort to a warrant.
10 Riley v. California, 573 U.S. 373 (2014); United States v. Jones, 565 U.S. 400 (2012).
11 Riley, 573 U.S. at 373.
12 The court noted that a smartphone was “a cell phone with a broad range of other functions based on advanced computing capability, large storage capacity, and Internet connectivity.” Riley, 573 U.S. 373.
13 Riley, 573 U.S. 373.
14 Jones, 565 U.S. 400.
15 “We are not unaware of the threat to privacy implicit in the accumulation of vast amounts of personal information in computerized data banks or other massive government files.” Whalen v. Roe, 429 U.S. 589, 605 (1977).
16 International Association of Chiefs of Police, IACP Technology Policy Framework (2014).
Please cite as:
Donald R. Zoufal, “The Long and Winding Road: Understanding Legal Trends for Evaluating Emerging Technologies,” Police Chief Online (March 2020).
