Using Drug-Sniffing Dogs and Canine Units
It may seem a little invasive, but schools are permitted to use drug dogs to sniff out contraband during unannounced, random searches. And even though the Fourth Amendment prohibits unreasonable search and seizure, the use of drug-sniffing dogs in schools is permitted because students do not have a reasonable expectation of privacy in the school. Additionally, the courts have acknowledged that schools have a compelling interest in maintaining a drug-free environment.
But as with most Fourth Amendment issues, the legality of these types of drug searches has been largely shaped by the courts and remains in flux. This article explains the legality of using drug-sniffing dogs (or K-9 units) in schools.
Drug Dogs and the Meaning of 'Search'
In 2013, the U.S. Supreme Court (Florida v. Jardines) ruled that the use of a drug-sniffing dog on a homeowner's porch with the intention of investigating the contents of the home was a "search" in the context of the Fourth Amendment. This is an important distinction, since an official police search requires a warrant. Prior Court opinions have consistently gone the other way, citing the "plain view" (or "plain sniff") doctrine that permits the collection of evidence that is left out in the open. Incriminating smells that can be detected only by trained dogs were once considered fair game as long as the police had probable cause.
The Court's decision doesn't apply to public places or buildings (public and private) to which the drug dog and its handler are lawfully admitted. In other words, it is not a "search" within the context of the Fourth Amendment when a K-9 unit is invited into the school for a random drug search. While the Supreme Court has not specifically addressed the issue, federal courts have consistently upheld the constitutionality of random, unannounced drug searches in schools.
Drug Dogs and a Reasonable Expectation of Privacy
Bringing a drug-sniffing dog onto someone's porch is a search (requiring a warrant) because people have a reasonable expectation of privacy in their own homes. The same cannot be said of public schools, where students do not have a reasonable expectation of privacy. When drug dogs are used to search for contraband in schools, police are careful not to open backpacks or inspect students' belongings unless the dog signals that drugs are present.
While drug dogs are becoming more and more commonplace in our public schools, interpretations of the Fourth Amendment are constantly being challenged in the courts.