The Exterior Access Doctrine: Probable Cause to Search Vehicle Trunks under the Automobile Exception

Introduction

This case, The People of the State of Colorado v. Sheron Mario Furness (2025 CO 16), arises from an interlocutory appeal by the prosecution from a district court’s order suppressing all evidence found in the trunk of the defendant’s vehicle following a warrantless search. The defendant, Sheron Mario Furness, was confronted by Arapahoe County deputies after a nearby gunshot incident. At the scene, officers discovered a variety of items in plain view inside Furness’s car and then decided to search the trunk. The district court suppressed the trunk evidence on the ground that officers lacked probable cause to search a locked trunk that could not be accessed from the passenger compartment. The Colorado Supreme Court reversed, establishing a new precedent—now termed the “Exterior Access Doctrine”—that officers may infer trunk access from exterior circumstances and thus satisfy probable cause under the automobile exception, even if the trunk itself is locked.

Summary of the Judgment

Justice Berkenkotter, writing for a unanimous en banc court, held that under the totality of the circumstances, the officers reasonably believed the trunk contained evidence of a crime and thus had probable cause for a warrantless search. Key facts included: Furness’s proximity to the trunk at first contact, recovered car keys at the shooting scene, visible gun case in the backseat, open windows when officers arrived, and a witness identification of Furness as the shooter. Rejecting the district court’s focus on physical access from the passenger compartment, the Supreme Court concluded that Furness could have accessed the trunk from outside the vehicle and thus it was reasonable to search it without a warrant. The court reversed the suppression order and remanded for further proceedings.

Analysis

1. Precedents Cited

a. California v. Acevedo (500 U.S. 565, 1991): Established that when officers have probable cause to search a vehicle, they may search any container within it that could conceal evidence.

b. United States v. Ross (456 U.S. 798, 1982): Clarified that probable cause to search a vehicle extends to all compartments where contraband might be hidden, including the trunk, defined by the object of the search.

c. Maryland v. Dyson (527 U.S. 465, 1999): Confirmed that no separate exigency is needed for a readily mobile vehicle when there is probable cause for search.

d. People v. Mendez (986 P.2d 275, Colo. 1999) and People v. Zuniga (372 P.3d 1052, Colo. 2016): Emphasized the totality-of-the-circumstances test for probable cause and rejected bright-line rules.

e. People v. Cox (401 P.3d 509, Colo. 2017) and People v. Haggart (533 P.2d 488, Colo. 1975): Upheld warrantless trunk searches when probable cause existed under similar totality analyses.

2. Legal Reasoning

The court first reaffirmed the constitutional framework: warrantless searches are per se unreasonable absent probable cause and an applicable exception (U.S. Const. amend. IV; Colo. Const. art. II, § 7). The automobile exception permits a warrantless search of a vehicle when officers reasonably believe it contains evidence of a crime, without a separate exigency requirement (Dyson).

Applying Ross and Acevedo, the court held that once probable cause justifies searching a vehicle, it justifies searching every compartment where the object of the search—here, the firearm used in a shooting—might be hidden. The district court’s narrow focus on interior access ignored the officers’ reasonable inference that Furness could open the trunk from outside or via the open windows present at first contact.

Under Illinois v. Gates (462 U.S. 213, 1983), probable cause turns on a common-sense, totality-of-the-circumstances inquiry. Here, the combination of (1) Furness’s presence at the shooting scene, (2) discovery of his keys near where the shots were fired, (3) his proximity to the trunk, (4) the open windows, (5) the visible gun case, and (6) a witness’s positive identification, all pointed to a fair probability that the trunk concealed the weapon. The locked status of the trunk, without any evidence of a lock at the moment of the offense, did not eliminate that probability.

3. Impact

The Supreme Court’s decision clarifies that probable cause for an automobile search is not defeated by a locked compartment if officers have a reasonable basis to believe the suspect could have accessed that compartment from the exterior. Lower courts will now apply the Exterior Access Doctrine to evaluate trunk searches, focusing on circumstantial and observational evidence rather than rigid notions of interior reachability. This doctrine strengthens law enforcement’s ability to gather evidence in mobile contexts but also underscores the continuing need for a robust totality-of-the-circumstances analysis to protect Fourth Amendment rights.

Complex Concepts Simplified

1. Automobile Exception: A legal rule allowing police to search a car without a warrant if they have probable cause to believe it contains contraband or evidence of a crime.

2. Probable Cause: A reasonable belief, based on facts and circumstances, that a crime has been committed or that evidence of a crime is present in a specific location.

3. Totality of the Circumstances: A flexible, common-sense approach to determining probable cause by considering all relevant facts together, rather than applying fixed rules.

4. Warrantless Search: A search conducted without a judicially issued warrant; generally disallowed unless an exception (like the automobile exception) applies.

5. Exterior Access Doctrine (newly articulated): Even if a vehicle’s trunk is locked, officers may infer access from outside based on circumstantial evidence—such as open windows or proximity to the trunk—supporting probable cause to search it.

Conclusion

The People of the State of Colorado v. Sheron Mario Furness establishes an important refinement of the automobile exception: officers may infer a suspect’s exterior access to locked compartments and thereby obtain probable cause to search the entire vehicle, including the trunk. By emphasizing the totality-of-the-circumstances approach and rejecting formal limitations on compartmental reachability, the Colorado Supreme Court has provided clear guidance for future trunk-search cases. This decision underscores that probable cause is a practical inquiry grounded in everyday life and reinforces the balance between effective law enforcement and constitutional privacy protections.