University of Chicago Law School Chicago Unbound Journal Articles Faculty Scholarship 2016 The Positive Law Model of the Fourth Amendment William Baude James Y. Stern Follow this and additional works at: https://chicagounbound.uchicago.edu/journal_articles Part of the Law Commons Recommended Citation William Baude & James Stern, "The Positive Law Model of the Fourth Amendment," 129 Harvard Law Review 1821 (2016). This Article is brought to you for free and open access by the Faculty Scholarship at Chicago Unbound. It has been accepted for inclusion in Journal Articles by an authorized administrator of Chicago Unbound. For more information, please contact [email protected]. VOLUME 129 MAY 2016 NUMBER 7 © 2016 by The Harvard Law Review Association ARTICLE THE POSITIVE LAW MODEL OF THE FOURTH AMENDMENT William Baude & James Y. Stern CONTENTS INTRODUCTION .......................................................................................................................... 1824 I. THE POSITIVE LAW MODEL ............................................................................................ 1829 A. Mechanics ........................................................................................................................ 1829 B. Distinguishing the Trespass Theory .............................................................................. 1833 II. THE CASES FOR THE POSITIVE LAW MODEL............................................................. 1836 A. History .............................................................................................................................. 1837 B. Structure .......................................................................................................................... 1841 C. Legality and Government Power ................................................................................... 1845 D. Practical Advantages ...................................................................................................... 1850 1. Clarity ......................................................................................................................... 1850 2. Adaptability ................................................................................................................ 1851 3. Institutions ................................................................................................................. 1852 E. Privacy and Beyond ....................................................................................................... 1855 F. Objections ........................................................................................................................ 1858 1. Mutability ................................................................................................................... 1858 2. Administrability ......................................................................................................... 1860 3. Baselines ..................................................................................................................... 1864 4. Endogeneity ................................................................................................................ 1866 III. THE POSITIVE LAW MODEL IN ACTION ...................................................................... 1867 A. Explaining Current Law ................................................................................................ 1867 B. Sorting Out Three-Body Problems ............................................................................... 1871 1. Third-Party Doctrine ................................................................................................ 1871 2. First- and Third-Party Consent ............................................................................... 1876 3. Additional “Standing” Requirements? .................................................................... 1880 C. Revising Current Law .................................................................................................... 1881 1. Abandonment ............................................................................................................. 1881 2. Drones ......................................................................................................................... 1883 3. Seizures ....................................................................................................................... 1884 4. Open Fields Reconsidered ........................................................................................ 1886 1821 1822 HARVARD LAW REVIEW [Vol. 129:1821 D. Implementing the Positive Law Model ........................................................................ 1887 IV. CONCLUSION ....................................................................................................................... 1888 ARTICLE THE POSITIVE LAW MODEL OF THE FOURTH AMENDMENT William Baude & James Y. Stern For fifty years, courts have used a “reasonable expectation of privacy” standard to define “searches” under the Fourth Amendment. As others have recognized, that doctrine is subjective, unpredictable, and conceptually confused, but viable alternatives have been slow to emerge. This Article supplies one. We argue that Fourth Amendment protection should be anchored in background positive law. The touchstone of the search-and-seizure analysis should be whether government officials have done something forbidden to private parties. It is those actions that should be subjected to Fourth Amendment reasonableness review and the presumptive requirement to obtain a warrant. In short, Fourth Amendment protection should depend on property law, privacy torts, consumer laws, eavesdropping and wiretapping legislation, anti-stalking statutes, and other provisions of law generally applicable to private actors, rather than a freestanding doctrine of privacy fashioned by courts on the fly. This approach rests on multiple grounds. It is consistent with the history of the Fourth Amendment and with the structure of protection in the closely related area of constitutional property. It draws upon fundamental principles of liberal constitu- tionalism, namely a concern about abuse of official power. And it is superior to current privacy-based doctrine in many practical ways: it is clearer, more predictable, more accommodating of variation in different times and places, and more sensitive to the institutional strengths of legislative bodies, particularly when it comes to issues presented by new technologies. It also has significant doctrinal implications. Of most immediate importance, it provides a framework to analyze third-party problems — situations in which information about one person is obtained from another — that is more coherent and more attractive than the modern third-party doctrine. It also provides a new framework for many other contested Fourth Amendment questions, from abandoned property and DNA to the use of drones. ––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– Neubauer Family Assistant Professor of Law, University of Chicago Law School; and Assis- tant Professor of Law, William & Mary Law School. Our greatest thanks to Richard Re, who motivated us to begin and to complete this project even as he declined to coauthor it. Great thanks as well to Aakshita Bansal, Hannah Cook, and Laura Worden for helpful research assistance, and to the SNR Denton and Alumni Faculty Funds at the University of Chicago Law School for research support. Further thanks to Aditya Bamzai, Jeff Bellin, Samuel Bray, Nathan Chapman, Kevin Cole, Laura Donohue, Donald Dripps, Barry Friedman, Adam Gershowitz, John Harrison, Daniel Hemel, Aziz Huq, Orin Kerr, Jonah Knobler, Randy Kozel, Saul Levmore, Michael Mannheimer, Richard McAdams, Judith Miller, Martha Nussbaum, David Pozen, John Rappaport, Laurent Sacharoff, Mike Seidman, David Sklansky, Geof Stone, Lior Strahilevitz, Lee Strang, David Strauss, Matthew Tokson, and workshop participants at Notre Dame, Georgetown, and the University of Chicago for generous and trenchant comments. In memoriam P.L.B. and R.E.M.: haeres est alter ipse, et filius est pars patris. 1823 1824 HARVARD LAW REVIEW [Vol. 129:1821 INTRODUCTION he touchstone of Fourth Amendment analysis,” the Supreme “ TCourt has told us, “is whether a person has a ‘constitutionally protected reasonable expectation of privacy.’”1 Such statements must be taken with a few grains of salt. The Fourth Amendment protects against searches and seizures, but reasonable expectations of privacy have almost nothing to do with what qualifies as a seizure.2 Even for searches, the Court’s declaration is more than a little misleading. It is, frankly, a truism that privacy is at stake when it comes to deciding what actions count as Fourth Amendment “searches”: to restrict the ability of government agents to act in ways likely to reveal information is necessarily to increase privacy. The real issue isn’t whether some piece of information or place is in fact private but whether it should be. Privacy is the answer to be given, not the question to be asked; the effect, not the cause. In practice, therefore, the fulcrum of the “reasonable expectation of privacy” doctrine ends up being “reasonable,” not “privacy.” And rea- sonableness reduces either to a difficult empirical question about intui- tions and social norms (those expectations “society is prepared to rec- ognize as ‘reasonable’”3) or to a largely open-ended policy judgment (those expectations