U.S. Supreme Court issues two opinions on drug sniffing dog searches

The U.S. Supreme Court has issued a series of decisions recently regarding the legality of police searches which resulted from drug-detecting dog alerts and led to the arrest of a suspect.

Under the Fourth Amendment, U.S. citizens have a right to privacy and are free from unreasonable searches and seizures. Police therefore cannot search people or their homes without a warrant or a person’s consent to search for drugs.

The exception is if police have “probable cause” to conduct a search. Case law is extensive on what this means, and courts rule on this issue on a case-by-case basis, but generally probable cause results from a “fair probability” that illegal activity is taking place or that there is illegal contraband on a premises or individual.

One method police use to determine whether there is probable cause for a search is if a drug-sniffing dog “alerts” the police that it smells illegal drugs inside a home or vehicle. Police cannot use dogs to conduct a search without a warrant, but if a person does not have an expectation of privacy, for instance if that person is out in public, then a dog can alert police and police can subsequently conduct a search that does not violate the constitution. This is a nuanced area of the law and the U.S. Supreme Court has often weighed in on the issue. Two such cases recently clarified certain aspects of what amounts to a search under the Fourth Amendment.

Drug detecting dogs are not infallible, and certain dogs are more accurate when detecting drugs than others. In one case brought before the nation’s highest court, police pulled over a man during a routine traffic stop. The officer’s dog signaled the presence of drugs in the trunk; there were no drugs in the vehicle, but there was pseudoephedrine and other ingredients used to make methamphetamine. The dog was not trained to detect meth.

Police arrested the man, and the defendant argued that the officer did not have probable cause to conduct the search because the dog was not trained to detect meth and because police did not keep records of how many times the dog had falsely alerted police to the presence of drugs. The Florida Supreme Court agreed with the defendant.

The U.S. Supreme Court, in its decision, overturned the Florida Supreme Court, holding that because training and testing records supported the dog’s ability, the evidence could be used in court, meaning that the officer did have probable cause to conduct a search.

Courts have traditionally found that people in their homes have a greater expectation of privacy than in vehicles. In another case decided in March, the Supreme Court found that a dog sniff search conducted on the front porch of a home amounted to a search under the Fourth Amendment. Justice Scalia wrote that police can go up to a home and knock on the front door, since all citizens can do that, but that “introducing a trained police dog to explore the area around the home in hopes of discovering incriminating evidence is something else.”

Whether police have probable cause to conduct a search is a complicated but incredibly important part of any criminal prosecution, as any evidence police obtain in violation of the constitution cannot be introduced in court. People accused of drug possession, distribution or trafficking should contact a skilled criminal defense attorney to ensure that their rights are protected.