Sniffing out our Fourth Amendment rights

Does a police dog sniffing for drugs at a suspect's front door constitute an illegal search? That's a question that the U.S. Supreme Court will consider in the case of Florida v. Jardines.

The Fourth Amendment of the U.S. Constitution protects against unreasonable searches of people and property. A "search" occurs when the government intrudes upon an individual's reasonable expectation of privacy. To have a reasonable expectation of privacy, the individual must have actually expected privacy and that expectation must be one that society recognizes as reasonable. A government search is unreasonable if it is conducted without a search warrant that is supported by probable cause of wrongdoing.

In Florida v. Jardines, police received an anonymous tip that marijuana was growing at Joelis Jardines's home. To investigate, law enforcement went to the house to observe it with officers from several law enforcement agencies and multiple vehicles, a process that took several hours. During that time, a trained drug-sniffing dog and his handler approached the front door, and the dog signaled the presence of narcotics in the home. Based in large part on the dog's alert, law enforcement obtained a search warrant for the house, found marijuana and arrested Jardines. The Supreme Court now must decide whether or not the dog sniff required a search warrant supported by probable cause.

The court previously has considered whether dog sniffs constitute searches in a few situations that did not involve people's homes. These cases provide some insight into the issues the court may consider in deciding Jardines. For example, the court determined that dog sniffs do not require warrants when the target is personal luggage in an airport (United States v. Place, 1983) or is the outside of a car either during a legal traffic stop (Illinois v. Cabelles, 2005) or at a roadside drug checkpoint (City of Indianapolis v. Edmond, 2000). Across these cases, the court reasoned that the dog sniffs did not invade privacy because they only revealed the presence of contraband, and individuals do not have a legitimate expectation of privacy in the possession of illegal material. The sniffs did not intrude on non-contraband private property or activities. The court considered the level of embarrassment that could result from the dog sniff, reasoning that a sniff may be more intrusive if the sniffed person is identifiable and publically humiliated. The court also considered whether allowing dog sniffs in these circumstances would result in arbitrary or discriminatory searches. These and other factors may play a role in the court's reasoning about Jardines. The court also is likely to consider the sacrosanct nature of the home under the Fourth Amendment.

Psychological research can help inform courts' reasoning on these issues. For example, research could investigate whether people have a reasonable expectation of privacy at their doorsteps; whether people have a different expectation of privacy for their doorsteps that would distinguish this case from past cases; whether people would be embarrassed by a dog-sniffing procedure like the one used in this case; and whether it is likely that such a procedure would be used arbitrarily. Some relevant research found that people rank a dog sniffing a person's body as just as intrusive as a police frisk, which indicates that warrantless dog sniffs may be perceived as unreasonable (Blumenthal, Adya, & Mogle, 2009; Slobogin & Schumacher, 1993). However, research has not investigated perceptions of dog sniffs of property or homes. Other research indicates that when the decision to search is discretionary, there is a potential for a discriminatory search (Rojek, Rosenfeld & Decker, 2004). However, more research is needed to identify potential biases and stereotypes that may lead to discriminatory application of searches and seizures. Further research on these issues may help judges evaluate the validity of dog sniffs and other searches.

"Judicial Notebook" is a project of APA Div. 9 (Society for the Psychological Study of Social Issues).