The Moving Property Problem in Fourth Amendment Law

*Stella W. and Ira S. Lillick Professor of Law, Stanford Law School. An early version of this Article was presented at Yale Law School for the 2024 Michael A. Doyle ʼ62 and Bunny Winter Distinguished Visiting Professor of Law Lecture. Thanks to Heather Gerken, Justin Driver, Kate Stith, Jonathan Macey, and Robert Weisberg for comments.Show More

Introduction

Imagine you are carrying a bag that the police want to search. The Fourth Amendment rules for searching your bag depend on where it is. If the bag is inside your home, the government needs a warrant to enter the home and search it.¹ 1.See Silverman v. United States, 365 U.S. 505, 512 (1961) (holding that physical entry requires a warrant). The Supreme Court first expressly so held in Agnello v. United States, 269 U.S. 20, 31–33 (1925), although the point had “always been assumed.” Id. at 32.Show More If the bag is in your car, however, probable cause is enough, and no warrant is needed.² 2.See California v. Acevedo, 500 U.S. 565, 579–80 (1991) (holding that a search of property placed in a car requires probable cause but not a warrant).Show More If the police arrest you while you’re carrying the bag, they can search the bag without any cause.³ 3.See United States v. Robinson, 414 U.S. 218, 236 (1973) (allowing the search of property on a person based on lawful arrest alone without requiring additional cause).Show More If the bag is more than a few feet from you at the time of your arrest, however, the government needs a warrant again.⁴ 4.See Chimel v. California, 395 U.S. 752, 763 (1969) (holding that a search incident to arrest only extends to the area of immediate control around the person arrested).Show More As these examples suggest, Fourth Amendment protection is fundamentally place-based. The government’s search power depends on where items to be searched are located.

The place-based nature of Fourth Amendment rules raises a question: If property is moved to a new place, does moving the property change its constitutional protection? In other words, are search and seizure protections fixed using an item’s prior location, or do those protections vary when the item is brought somewhere new? This question comes up often in Fourth Amendment cases. Consider a few examples drawn from recent decisions:

An officer orders a passenger out of a car during a traffic stop. The passenger exits, taking her purse with her. Searching a purse outside a car requires a warrant, but searching a purse inside a car does not. Is a warrant needed to search the purse after the passenger has removed it from the car?⁵ 5.See State v. Lang, 942 N.W.2d 388, 400 (Neb. 2020), discussed in Section I.B.Show More

The federal government has broad power to search at the border. Border agents seize a suspect’s computer at the border, but they lack the expertise to search it. Agents bring the computer to a forensics expert, located hundreds of miles from the border, who searches it at his office. Does the forensic expert’s search count as a border search?⁶ 6.See United States v. Cotterman, 709 F.3d 952, 961–62 (9th Cir. 2013) (en banc), discussed in Section I.D.Show More

Officers want to arrest a suspect at his home, but they lack the warrant needed to enter the home to arrest him inside. From their position outside, officers point their guns at the suspect inside and order him to leave his house. He complies with the order, and officers arrest him outside. Was a warrant needed?⁷ 7.See United States v. Maez, 872 F.2d 1444, 1450–51 (10th Cir. 1989), discussed in Section I.C.Show More

Police arrest a man wearing a fanny pack. For their own safety, officers remove the fanny pack and place it twenty feet away. The Fourth Amendment permits a warrantless search of property on the person incident to his arrest, but it does not allow a search of property more than a few feet away. Can the police still search the fanny pack without a warrant?⁸ 8.See, e.g., Jean v. State, 369 So. 3d 1235, 1237–38 (Fla. Dist. Ct. App. 2023). This scenario is discussed in Section I.B.Show More

Investigators have a warrant to search a house, but they lack the cause needed to detain and interrogate a particular suspect who lives there. They know, however, that Fourth Amendment law allows the government to detain anyone present when a warrant is executed. Hoping to interrogate the suspect, investigators contact the suspect and pretend that his house has been robbed and that he should come home to assess the damage. When the man arrives, officers detain and interrogate him. Was this lawful?⁹ 9.See United States v. Ramirez, 976 F.3d 946, 949–50 (9th Cir. 2020), discussed in Section I.C.Show More

The driver of a car consents to its search. An officer orders everyone out of the car, and a passenger takes her purse with her. The officer orders the passenger to put her purse back in the car so it can be searched. Case law allows the government to search anything in the car with the driver’s consent but requires a warrant to search a purse outside the car. Can officers search the purse?¹⁰ 10.See State v. Boyd, 64 P.3d 419, 427 (Kan. 2003), discussed in Section I.C.Show More

In each of these cases, something or someone was moved from one place governed by one rule to a new place governed by a different rule. Sometimes the government moved the relevant thing or person. Sometimes a private party did. And sometimes the government caused the private party to move it. Each case raises the same question: Does moving the item to a new place change its constitutional protection?

I call this the moving property problem.¹¹ 11.By the phrase “moving property,” I mean anything that can be moved and that can later be searched, whether or not it counts as property in a technical legal sense. In most cases, the moving property will be containers such as bags, purses, briefcases, and fanny packs. In some cases, the item moved is a person, who is moved away from their containers or who is moved to a different location and then searched. I consider all of these examples of the moving property problem.The label “moving property problem” might call to mind the automobile exception to the warrant requirement, under which searching a car does not require a warrant in part because cars are readily movable. See, e.g., California v. Carney, 471 U.S. 386, 390–91 (1985). My concern in this Article is not with whether property should receive different protection because it can move, however, but whether protections should change when items are moved from a place governed by one rule to a place governed by a different rule. Some moving property cases involve the automobile exception, as property is readily placed into or taken out of cars. But the moving property problem is about the clash of rules between two places—akin to a conflict of law problem—not the rules of any one place.Show More Despite how often it surfaces, neither courts nor scholars have recognized it.¹² 12.My research has uncovered no prior articles on the moving property problem. The most relevant scholarship appears to be several articles on one specific application—whether and when officers can make warrantless doorway arrests by moving arrestees out of the home. There is a narrow literature on that question. See, e.g., Jack E. Call, The Constitutionality of Warrantless Doorway Arrests, 19 Miss. Coll. L. Rev. 333, 334–36 (1999) (discussing the cases); Steven B. Dow, “Step Outside, Please”: Warrantless Doorway Arrests and the Problem of Constructive Entry, 45 New Eng. L. Rev. 7, 18–23 (2010) (same). See generally 3 Wayne R. LaFave, Search and Seizure § 6.1(e) (6th ed. 2020) (“Location of the arrestee: ‘at,’ ‘on’ and past the threshold.”). For a discussion of the relevant cases, see infra Section I.C.Show More The moving property problem is particularly rich because the ex ante incentives are obvious. Government agents want to expand their search power, just as targets of searches want that authority narrowed.¹³ 13.The two sides are not equal in the likelihood that they intend to use the Fourth Amendment’s rules to their advantage. The police are trained in the rules, and the cases show them intentionally seeking to manipulate the rules in their favor. In contrast, few individuals will have the knowledge and foresight to know and use the rules.Show More If Fourth Amendment case law allows it, the police will move property or suspects to a place where officers have greater power to search—and then search under the relaxed rules of the new place. On the flip side, private parties who know the law may want to move their property to a place where their privacy rights are greatest—impeding investigations, if they can, by triggering the more restrictive rules of the new location. Ex post litigation incentives are clear, too. Each side has reason to argue that the other’s moving of property works in reverse. When a suspect happens to move his property to a place where rights are weaker, the government will argue that rules of the new location apply. And defendants will make the mirror-image argument when police move property to a place where rights are stronger.¹⁴ 14.See infra Part I.Show More

This Article offers a comprehensive study of the moving property problem in Fourth Amendment law. It has two goals, one descriptive and one normative. The descriptive goal is to show that a large set of cases, not previously linked, all raise this common dynamic. Cataloging the many moving property cases reveals a taxonomy with variations on a theme.¹⁵ 15.See infra Part I.Show More It also shows that Supreme Court decisions rarely answer how to resolve moving property questions. In the absence of high court guidance, lower courts have struggled for answers. They have treated each case in isolation, and they have often disagreed on the correct approach. The lower court disagreement results from a failure to see and appreciate the moving property problem.

The second goal of this Article is to offer a normative framework for solving the moving property problem. It has two steps. The first step is to recognize why Fourth Amendment rules are spatially based in the first place. The Fourth Amendment’s text, history, and case law seek to protect particular spaces in particular ways.¹⁶ 16.See infra Section II.A.Show More The rules recognize how different interests compete differently in different areas. This understanding prompts an initial answer to moving property problems. To decide whether movement changes the level of protection, courts should answer whether the movement aligns with the justifications for the Fourth Amendment’s location-based rules. Courts must look doctrine-by-doctrine, focusing on the reasons for the space-based rules in play and the role of movement in supporting or defeating those reasons.¹⁷ 17.See infra Section II.B.Show More

The second step is realizing that some moving property cases raise two questions instead of one. When the government causes movement, either directly or by creating pressures on private parties to act, a second question must also be considered: Was the government-induced movement itself illegal, apart from the subsequent search? Government agents can be endlessly creative in devising new ways to get property to places where government search powers are greatest.¹⁸ 18.Cf. Johnson v. United States, 333 U.S. 10, 14 (1948) (Jackson, J.) (noting that the Fourth Amendment generally requires that “those inferences be drawn by a neutral and detached magistrate instead of being judged by the officer engaged in the often competitive enterprise of ferreting out crime”).Show More In many of these cases, the legal limits in moving property cases should come not from the legal rule for searching at the old or new place but from recognizing the illegality of steps taken to trigger the movement itself.¹⁹ 19.See infra Section II.E.Show More

The Article proceeds in two parts. Part I offers a taxonomy of existing cases. It lays out the four basic kinds of moving property cases, explaining the scenarios and surveying how courts have so far resolved them. Part II proposes answers, developing a framework for solving the moving property problem and providing rules that courts can adopt to address them.

1.  See Silverman v. United States, 365 U.S. 505, 512 (1961) (holding that physical entry requires a warrant). The Supreme Court first expressly so held in Agnello v. United States, 269 U.S. 20, 31–33 (1925), although the point had “always been assumed.” Id. at 32. ↑
2.  See California v. Acevedo, 500 U.S. 565, 579–80 (1991) (holding that a search of property placed in a car requires probable cause but not a warrant). ↑
3.  See United States v. Robinson, 414 U.S. 218, 236 (1973) (allowing the search of property on a person based on lawful arrest alone without requiring additional cause). ↑
4.  See Chimel v. California, 395 U.S. 752, 763 (1969) (holding that a search incident to arrest only extends to the area of immediate control around the person arrested). ↑
5.  See State v. Lang, 942 N.W.2d 388, 400 (Neb. 2020), discussed in Section I.B. ↑
6.  See United States v. Cotterman, 709 F.3d 952, 961–62 (9th Cir. 2013) (en banc), discussed in Section I.D. ↑
7.  See United States v. Maez, 872 F.2d 1444, 1450–51 (10th Cir. 1989), discussed in Section I.C. ↑
8.  See, e.g., Jean v. State, 369 So. 3d 1235, 1237–38 (Fla. Dist. Ct. App. 2023). This scenario is discussed in Section I.B. ↑
9.  See United States v. Ramirez, 976 F.3d 946, 949–50 (9th Cir. 2020), discussed in Section I.C. ↑
10.  See State v. Boyd, 64 P.3d 419, 427 (Kan. 2003), discussed in Section I.C. ↑
11.  By the phrase “moving property,” I mean anything that can be moved and that can later be searched, whether or not it counts as property in a technical legal sense. In most cases, the moving property will be containers such as bags, purses, briefcases, and fanny packs. In some cases, the item moved is a person, who is moved away from their containers or who is moved to a different location and then searched. I consider all of these examples of the moving property problem.

    The label “moving property problem” might call to mind the automobile exception to the warrant requirement, under which searching a car does not require a warrant in part because cars are readily movable. See, e.g., California v. Carney, 471 U.S. 386, 390–91 (1985). My concern in this Article is not with whether property should receive different protection because it can move, however, but whether protections should change when items are moved from a place governed by one rule to a place governed by a different rule. Some moving property cases involve the automobile exception, as property is readily placed into or taken out of cars. But the moving property problem is about the clash of rules between two places—akin to a conflict of law problem—not the rules of any one place. ↑

12.  My research has uncovered no prior articles on the moving property problem. The most relevant scholarship appears to be several articles on one specific application—whether and when officers can make warrantless doorway arrests by moving arrestees out of the home. There is a narrow literature on that question. See, e.g., Jack E. Call, The Constitutionality of Warrantless Doorway Arrests, 19 Miss. Coll. L. Rev. 333, 334–36 (1999) (discussing the cases); Steven B. Dow, “Step Outside, Please”: Warrantless Doorway Arrests and the Problem of Constructive Entry, 45 New Eng. L. Rev. 7, 18–23 (2010) (same). See generally 3 Wayne R. LaFave, Search and Seizure § 6.1(e) (6th ed. 2020) (“Location of the arrestee: ‘at,’ ‘on’ and past the threshold.”). For a discussion of the relevant cases, see infra Section I.C. ↑
13.  The two sides are not equal in the likelihood that they intend to use the Fourth Amendment’s rules to their advantage. The police are trained in the rules, and the cases show them intentionally seeking to manipulate the rules in their favor. In contrast, few individuals will have the knowledge and foresight to know and use the rules. ↑
14.  See infra Part I. ↑
15.  See infra Part I. ↑
16.  See infra Section II.A. ↑
17.  See infra Section II.B. ↑
18.  Cf. Johnson v. United States, 333 U.S. 10, 14 (1948) (Jackson, J.) (noting that the Fourth Amendment generally requires that “those inferences be drawn by a neutral and detached magistrate instead of being judged by the officer engaged in the often competitive enterprise of ferreting out crime”). ↑

19.  See infra Section II.E. ↑