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The Constitutional Validity of the Random K-9 Search



By: David Zwanetz, Esq.

First off, it is imperative to know that the Fourth Amendment to the United States Constitution secures the “right of all people to be secure in their persons, houses, papers and effects, against unreasonable searches and seizures,” and mandates that that right “shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the person or thing to be seized.”

That being said, one must understand that there are a number of exceptions to the warrant requirement that allow police to search and seize people and items without a written warrant.  To that effect, many courts, including the Supreme, have held that the sniff of a trained police dog dog not even constitute a search under the Fourth Amendment.

The purpose of this article is to discuss some of the more important aspects of search and seizure law as it specifically relates to police dogs.  Logic flows that if a police dog sniff is not a search than police would bring dogs to the scene of any suspicious stop to check for drugs, even if they otherwise have no probable cause for a warrant to search.  This is exactly what the Howard County police have begun to do.  The question is, is this legal/Constitutional?  The short answer is, as it usually is, that it depends.  The point of this article is to give a brief overview of the legality of the k-9 search, enough so that the average person can be at least slightly informed of his or her rights.  After all, our lives in this country are guided by the US Constitutional and its Amendments.  However, very few people, outside of the legal community, have a grasp on any of its provisions. As a Howard County criminal lawyer, it is my goal to change that.

Police dogs are a valuable asset for today’s law enforcement agencies.  Recent efforts to combat narcotics in growing rural areas like Howard County have led to an even greater role for the police dog.  Generally, courts have embraced the use of police dogs. As mentioned above, the Supreme Court has held that a dog sniff is not a search that requires probable cause.  In determining that the canine sniff is not a search under the Fourth Amendment, the Court relied upon the extremely limited nature of the intrusion and the fact that there is no expectation of privacy in the air or in an odor.  Courts have also noted that there is no actual physical intrusion in the area or article sniffed.  Nontneless, minimal physical contact between the dog and the article will not escalate the sniff to a Fourth Amendment “seizure.”


The principal that a police dog may sniff an area or article without a search warrant is considered analogous to the plain-view doctrine (which is essentially the idea that if the police see contraband in plain view they can seize it without a warrant) and has become known as the “plain-smell doctrine.”  The use of a dog’s keener sense of smell to detect odors is comparable to the use of an officer’s flashlight to enhance the officer’s perception of that which is already in plain view.

However, and most importantly, in order to utilize this plain-smell doctrine, the police must legitimately be at the location where the sniff occurs or legitimately detaining the article sniffed.  This brings me back to the idea of an officer calling a k-9 unit when he or she senses something suspicions during a routine traffic stop.  In order for the police to be considered “legally where they are,” during a traffic stop they must not hold a suspect during that traffic stop any longer than it would take an ordinary prudent officer to issue a citation for the underlying traffic offense.  Think of it this way.  The Fourth Amendment veil is like an iron curtain that opens only when probable cause or a warrant exists.  During a traffic stop the curtain opens so that the officer can issue a citation for whatever offense was committed (i.e., speeding, tail light out, running a stop sign, etc.). However, the curtain closes immediately upon the issuance of the citation or at the time when the citation should have been issued.

Thus, if an officer is able to have a k-9 unit do a perimeter search of one’s car during the small amount of time that it takes to issue a citation, the Fourth Amendment has been complied with. However, if an officer calls a k-9 unit upon suspicion and holds a suspect even one minute longer than the ordinary time to issue a citation waiting for that k-9 unit to arrive, the Fourth Amendment has been violated.  A violation of the Fourth Amendment will not stop an arrest from taking place, but it can and should lead to the suppression of evidence in court.  Additionally, there is nothing at all wrong with a suspect being issued a traffic citation refusing to wait for a  k-9 officer to arrive and do a random search – believe it or not that happens all the time.  This is essentially a person volunteering to wait to have his or her rights violated.

If your have been the subject of a K-9 search and you feel your rights have been violated, call the Howard County Criminal Attorneys at the law firm Shapiro Zwanetz & Lake (SZL) for a free and immediate consultation.