In Collins v. Virginia, decided in 2018, the U.S. Supreme Court ruled 8–1 that the Fourth Amendment’s automobile exception does not allow police to enter the curtilage of a home without a warrant to search a vehicle parked there.1Collins v. Virginia, decided by the Supreme Court in 2018, established that the Fourth Amendment’s automobile exception does not allow police to enter a home’s curtilage without a warrant to search a vehicle parked there. Justice Sonia Sotomayor wrote for the majority. Probable cause alone, the Court held, is not enough to justify crossing onto private residential property, no matter how strong the case for searching the vehicle itself.
What Happened
Two high-speed chases in Virginia involved a rider on a distinctive orange and black motorcycle with an extended frame. Officers believed the same person was responsible for both and began investigating. Officer David Rhodes eventually found a photograph on social media showing what looked like the motorcycle parked in the driveway of a house where Ryan Austin Collins’s girlfriend lived.
Rhodes drove to the house. From the street he could see a motorcycle under a white tarp at the top of the driveway, close to the home. The top of that driveway was enclosed on two sides by a brick wall about the height of a car and on the third side by the house itself. Without a warrant and without asking anyone’s permission, Rhodes walked up the driveway, lifted the tarp, and recorded the motorcycle’s license plate and vehicle identification number. It came back as stolen, and Collins was indicted for receiving stolen property.
Collins moved to suppress the evidence, arguing that Rhodes had trespassed onto the curtilage of the home to conduct a warrantless search. Virginia’s trial court, court of appeals, and supreme court all sided with the state, holding that the automobile exception justified the search because Rhodes had probable cause. The U.S. Supreme Court granted review and reversed.
Why the Automobile Exception Didn’t Reach the Driveway
The automobile exception dates back to Carroll v. United States in 1925. It lets officers search a vehicle without a warrant when they have probable cause to believe it contains evidence of a crime. Two justifications underlie the rule: vehicles are mobile and can be driven off before a warrant is issued, and they carry a reduced expectation of privacy because they travel on public roads and are subject to licensing and inspection. In California v. Carney (1985), the Court applied that reasoning to a motor home parked in a public lot, treating it as a vehicle rather than a residence.
Justice Sotomayor’s opinion drew a firm line at the edge of the home. Just as an officer needs a lawful right of access to seize contraband in plain view or to arrest someone inside a house, an officer needs a lawful right of access to the vehicle itself before invoking the automobile exception. Seeing the tarp from the street was fine. Walking up the driveway to lift it was a physical intrusion into constitutionally protected space.
The Court warned that expanding the exception to reach curtilage would “untether the exception from its justifications.” If probable cause alone let officers walk onto a driveway, the same logic would open garages, carports, and any other residential space where a vehicle might be kept. The scope of the automobile exception, the majority wrote, extends no further than the automobile itself.
Justice Samuel Alito dissented alone. He argued the search was reasonable because the motorcycle would have been fair game had it been parked a few feet away at the curb, and its brief walk up the driveway did not change its mobility or Collins’s privacy interest in its contents. The majority was unpersuaded: the boundary of the home is not measured in feet from the curb.
What Counts as Curtilage
Curtilage is the area immediately surrounding a home that people use for the ordinary activities of domestic life. For Fourth Amendment purposes, it is treated as part of the home and receives the highest level of constitutional protection. A front porch, a side garden, or a driveway next to the house typically qualifies.
The Court laid out a four-factor test in United States v. Dunn (1987) for deciding whether a specific area is curtilage:
- Proximity of the area to the home.
- Whether the area sits within an enclosure that also surrounds the home.
- How the area is used, particularly whether it is used for everyday domestic activities.
- What steps the resident has taken to shield the area from observation by people passing by.
Applied to Collins’s case, the top of the driveway was easy. It sat against the house, was walled off on two sides, and was the kind of space the Fourth Amendment was designed to protect. That designation, more than any dispute about the motorcycle itself, drove the outcome.
Curtilage has a counterpart called the open fields doctrine. Pastures, wooded tracts, vacant lots, and similar spaces receive no Fourth Amendment protection, even when fenced and posted with no-trespassing signs. A vehicle parked in an open field carries no protection for the surrounding land. A vehicle parked in curtilage does.
When Police Can Still Search a Vehicle at a Home
Collins did not put vehicles on residential property beyond the reach of police. The majority expressly left open that other warrant exceptions might justify a search in similar circumstances, and remanded Collins’s case for Virginia’s courts to consider whether exigent circumstances applied.
Exigent circumstances allow a warrantless search when an emergency leaves no time to obtain one. Recognized categories include:
- Hot pursuit of a fleeing suspect who runs onto private property.
- A reasonable belief that evidence is about to be destroyed or moved.
- An objectively reasonable belief that someone inside needs urgent help.
- Consent from the homeowner or another person with authority to give it.
The point of Collins is that the automobile exception is not itself one of those justifications when the vehicle sits in curtilage. Officers who spot a suspect vehicle in a driveway, with no emergency in play, need a warrant or an independent basis to approach it.
What Collins v. Virginia Means Now
Before this ruling, some lower courts had treated the automobile exception as a rule that followed the vehicle wherever it went. Collins closed that reading. The home and its curtilage hold a distinct place in Fourth Amendment law, and doctrines built for public roads do not migrate onto private residential property just because the target is a car or motorcycle.
For homeowners, the practical result is direct: police generally cannot walk up your driveway or into your carport to search a vehicle without a warrant, even when they have strong reason to believe the vehicle is tied to a crime. For officers, it means an added step when an investigation leads to a vehicle parked at a residence. Absent an emergency, consent, or another recognized exception, the correct move is to secure a warrant before crossing onto the property.