Privacy in Real Time

Updated Draft

-- By SidneyLee - 27 Nov 2024

Introduction

Technology has fundamentally changed our understanding of what it means to be observed in public–personal devices can now keep record of our location over time and personal information, and store such data indefinitely. Considering Katz, Riley, and Carpenter, is it “unreasonable” for the government to acquire digital information available on the open market? We are constantly revealing personal information through our personal devices, the law cannot assume that we automatically give up a reasonable expectation of privacy by using our phones, so integrated into modern daily life now, that inherently collect data on us. Cell phone users maintain a reasonable expectation of privacy such that law enforcement should be required to obtain a warrant before obtaining information from any third party.

Fourth Amendment Jurisprudence

Under the Fourth Amendment, “the right of people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated.” The Fourth Amendment was historically meant to protect individuals’ physical homes and property from indiscriminate searches and seizures that the colonists had experienced under the rule of British officers. The idea was that the Fourth Amendment protects only against physical intrusion into private spaces, but the Katz decision in 1967 held that “what [one] seeks to preserve as private, even in an area accessible to the public, may be constitutionally protected” (1). This represented an extension from the Fourth Amendment protecting physical, private spaces. The Katz test of intrusions into a reasonable expectation of privacy now forms modern Fourth Amendment jurisprudence.

The Fourth Amendment was born out of a desire to protect individuals from government intrusion into our private spaces. Katz has expanded the Fourth Amendment’s jurisdiction beyond physical trespass of homes and persons to protect individuals even when in public spaces. The historical origins of the Fourth Amendment and the Katz decision should lead us to the conclusion that the government should have to undergo legal processes to access data gained from cell phones even if it is available on an open market.

Warrants, Third-Party Doctrine, and Data Brokers

Although judges and legal scholars disagree over whether the Fourth Amendment actually contains a warrant requirement, in light of the legal landscape as it operates today, we will assume the constitutional status of the warrant requirement. Under Carpenter, the “third-party exception” to warrants does not apply to cell phone towers–law enforcement must obtain a warrant to access weeks-long records of historical CSLI (2). The third-party doctrine from United States v. Miller and Smith v. Maryland holds that individuals do not have an expectation of privacy in information voluntarily shared with third parties, whether or not they intended the government to have access to the data. The key concept in the third-party doctrine is that of “voluntariness.” With cell phones, individuals cannot be said to have voluntarily disclosed the myriad of personal information that phone technology collects and that data brokers share.

Real time location tracking enables law enforcement to monitor individuals through real-time tracking data bought from data brokers, often without warrants, because it is legal to collect, buy and sell such data (3). Apps regularly request location access from phone users, either to operate as intended (such as weather apps and navigation apps) or to suggest targeted advertising (all social media apps). However, these apps also have the ability to share location access data with third parties. Data brokers can pay app developers for this personal data, and are able to gather data whenever the app has access (4). This means that data brokers can also access location data whenever the app is being actively used, or even obtain background access to data even when the app is closed (4). Law enforcement accessing data from data brokers does not require a warrant. By “geofencing,” law enforcement are able to digitally “fence” a geographic area and then collect location data from everyone in that physical area (4). Geofencing still requires a warrant, but companies like Fog Data Science rely on advertising identification numbers, collected from numerous apps with targeted advertising, that escape the warrant requirement by maintaining “anonymity” of specific phone users (5).

The average cell phone user is unaware that their location tracking data is bought and sold by companies, and can be bought by law enforcement. Even if an individual is aware of these practices in the data market, individuals are not voluntarily giving information when the production and collection of such information is inescapable and automatic when phones unavoidably connect to nearby cell towers. Carpenter should be interpreted to protect real-time locking tracking data because it reveals the same type of “intimate window into a person’s life,” as held to be protected from a warrantless search by Carpenter. Specifically for geofence searches, the geofence warrants currently required should be held to a higher standard. Geofence warrants only specify a geographic location, but law enforcement at the time of the warrant do not specify a user or know if the user is going to turn up in the search (6).

Conclusion

As surveillance technology becomes more pervasive and more profitable, Fourth Amendment case law will have to keep pace with the growing technology. On April 17, 2024 the House passed the Fourth Amendment Is Not For Sale Act, which would “close the data broker loophole” by prohibiting intelligence agencies and law enforcement from purchasing data without a warrant (6). The Executive Office of the President issued a statement opposing the Act on the grounds that it would prohibit intelligence and law enforcement from “obtaining certain commercially available information” while leaving foreign adversaries free to obtain and use the same information (7). There is an argument to be made for balancing government power and individual privacy, but if the government truly has probable cause to investigate an individual then a warrant would be justified. Carpenter is a positive revision of the Fourth Amendment analysis for modern technology and its protection against warrantless searches should be expanded to the data brokerage market.