Police Dogs: The United States Supreme Court Revisits What Constitutes a “Search”

By Rudman Winchell Attorney

By: Rudman Winchell Attorney Colin E. Howard

The Fourth Amendment of the United States Constitution protects individuals from unreasonable searches and seizures. Generally, officers must have “probable cause,” and obtain a warrant before they are allowed to search your home. One reoccurring issue in this area of the law is what constitutes a “search.”

This past Wednesday, the United States Supreme Court heard two appeals regarding police dog searches. In Florida v. Jardines, the issue was whether a police dog sniffing around the outside of a house constitutes a search. In Florida v. Harris, the issues was whether police dogs are reliable detectors of drugs (Some evidence suggests that they are not, but that’s not the focus of this post.)

The Jardines appeal will likely require the Court to revisit its 2001 opinion, Kyllo v. United States. There, the Supreme Court decided that the use of thermal imaging goggles to investigate a home from the street constituted a search. The Court ruled that probable cause and a warrant are required before officers may train thermal imaging goggles at your home. An important point in Kyllo was that the thermal imaging goggles “invaded” the home because they allowed officers to detect heat through the walls. (The goggles are used to detect strong lightbulbs used to grow marijuana.) In contrast, regular surveillance with cameras does not constitute a search because it does not allow officers to see anything that a normal person would be able to, walking down the street. (Note that without a warrant, officers probably are not allowed to peer through the windows of a house with binoculars.)

The police in Jardines had led the dog, Franky, onto the property of the defendant because they were suspicious that drug activity was transpiring inside. After five to fifteen minutes of sniffing around the property, including up onto the house’s porch, Franky indicated that there were drugs inside. The officers obtained a warrant, and found marijuana.

At oral argument in Jardines, some of the Justices seemed to liken a police dog’s sensitive nose to the thermal imagining goggles. Both, they suggested, are invasive because the allow officers to detect evidence within the walls of a home that would otherwise be invisible. Justice Elena Kagan asked what would happen if the government “invented some kind of little machine called a ‘Smell-O-Matic'” that detected drugs like a dog? Wouldn’t that be the exact same as the thermal goggles, she wondered?

It is of course impossible to predict how the Court will decide the Jardines appeal. But it would seem consistent with Kyllo to rule that a drug-sniffing dog constitutes a search because, like the thermal imagining goggles, it effectively allows the government to peer inside the walls of a building.

The Jardines decision most likely will not affect the government’s ability to have a dog inspect your vehicle during a traffic stop. The Supreme Court has ruled that individuals have a lesser expectation of privacy in their cars.

A decision from the Court that police dogs sniffing around on your property constitutes a search will, however, affect some police departments’ plans to sweep neighborhoods with drug-detecting dogs by leading them up to each home’s front door.


These materials have been prepared by Rudman Winchell for educational purposes only. They should not be considered legal advice. The transmission of this information to you is not intended to create a lawyer-client relationship. Readers should not act upon this information without seeking professional counsel. You should not send any confidential or private information to Rudman Winchell until a formal attorney-client relationship has been established, in writing.