Traffic stops and the Fourth Amendment
A police officer sees a car run a stop sign. The officer puts on lights and siren and pulls over the car to give the driver a ticket. During this traffic stop, the officer somehow finds evidence of illegal drugs in the driver’s possession. Now, the driver faces not only a ticket for running a stop sign, but also serious drug charges.
Many drug crime cases begin like this, with a simple traffic stop. However, there are some important steps in between the moment when the officer spots the car and the moment the possibility of drug charges enters the picture. Some of those steps go right through the U.S. Constitution.
Unreasonable search and seizure
The Fourth Amendment to the U.S. Constitution provides that the people must be free of “unreasonable” search and seizure. In this context, “seizure” refers to arrest. Courts have interpreted the Fourth Amendment to mean that police generally must have a warrant to enter a person’s home to search through their belongings. A judge will issue a warrant after the police show they have probable cause to believe they will find evidence of a crime in their search.
There are many exceptions to this warrant requirement. For instance, if an officer sees evidence of a crime outside, the officer does not need a warrant to search. Likewise, if the resident of an apartment invites the police in, and the police see evidence inside the apartment, the police do not need a warrant to search the apartment and arrest the resident.
Searching a car
The situation is a little different when the police wish to search a car. A person has a reasonable expectation of privacy when they are in their home. They have less expectation of privacy when they are in a car. With this in mind, courts find that there is a somewhat blurry line between reasonable and unreasonable searches in a traffic stop.
If, during a traffic stop, while speaking to the driver, a police officer spots illegal drug paraphernalia and wads of cash sitting in plain view on the passenger seat, the officer does not need a warrant to begin searching further. A court would find that this search is reasonable.
When the suspect evidence is not in plain view, the reasonable/unreasonable question gets more difficult. A police officer at a routine traffic stop does not necessarily have the right to demand a driver open the car’s trunk. However, courts have found that walking a drug-sniffing dog around a car during a traffic stop is not an unreasonable search.
For people who are facing drug charges after a traffic stop, all this raises an important question: What happens if a police officer finds illegal drugs during an unreasonable search? The answer can depend on the exact circumstances of the case, but generally, this ill-gotten evidence cannot be used against the defendant in court. It must be suppressed from trial.
This is why one of the most powerful strategies in criminal defense is based on showing that the police exceeded their authority during the defendant’s search. If a defendant can show that the search violated their constitutional rights against unreasonable search, they can have the court suppress the evidence gathered during the search. Without this evidence, the prosecution may not be able to prove the drug charges against them.