Volume 44, Issue II
By Nicole Alexandra Plante*
This Note examines the application of third-party doctrine to location data and argues that the doctrine, as it currently stands, is unworkable in the modern digital era. Third-party doctrine holds that individuals forfeit Fourth Amendment protections when they voluntarily and knowingly share information with third parties, such as map or social media applications. However, individuals today routinely share sensitive location data with third parties, often without full awareness or meaningful consent. The Supreme Court acknowledged this challenge in Carpenter v. United States, carving out an exception for location information collected by cell towers, but failing to provide a clear framework for lower courts to apply.
This lack of guidance resulted in a circuit split between the Fourth and Fifth Circuits, each interpreting Carpenter to reach opposite conclusions on whether location data is voluntarily shared, followed by the Fourth Circuit subsequently rehearing the case and not reaching a majority on Carpenter and third-party doctrine. This circuit split, and subsequent indecision, highlights the challenge in applying third-party doctrine to location data and underscores the need for a new approach.
To resolve this issue, this Note proposes the Purpose-Sensitivity approach, a test that hinges Fourth Amendment protections on (1) whether the individual’s purpose in sharing their location data was to broadly share it with the public, and (2) whether the location data does or could contain sensitive information. This approach is both informed by the circuit courts’ reasoning and in line with Fourth Amendment jurisprudence, ensuring a more consistent and constitutionally sound application of third-party doctrine to location data. By refining the doctrine, this Note offers a solution that better balances individual privacy rights with law enforcement’s interests in the digital age.
* Yale Law School, J.D. expected 2026. I am deeply indebted to Professor Tracey Meares for cultivating my interest in criminal procedure and guiding me along the way. Without her guidance, thought-provoking questions, and support this Note would never have materialized. I want to thank Raymond Perez, Artha Jonassaint, Drew Jones, Priscilla Samey, and all the editors of Yale Law & Policy Review for their hard work and feedback during this process. To my family, thank you for your constant support throughout law school. And finally, thank you to Chase Hinman for your encouragement and insight. All views, errors, and omissions are my own.
