Police aren’t allowed to pull people over for just any reason. In the United States, we are protected by the Fourth Amendment, which prohibits unreasonable searches and seizures by government actors like the police. So, the police need a reason before they can prevent you from going about your business.
How good of a reason do the police need?
A pretty good reason. In Tennessee (and the rest of the federal Sixth Circuit), there are only three situations where police stops are allowed at all:
- The police are operating a constitutionally compliant sobriety checkpoint
- An officer has reasonable suspicion that ongoing criminal activity (including most traffic violations) is occurring
- An officer has probable cause to believe a civil violation (such as driving without insurance) has occurred
Probable cause is a higher standard than reasonable suspicion. Both mean that the officer has to have more than a hunch to meet their constitutional burden.
Police are trained on how to develop reasonable suspicion and probable cause in traffic cases. For reasonable suspicion, officers must be able to articulate some objective reason they think ongoing criminal activity or a traffic offense is happening. The reason must not be mere intuition, speculation, or discriminatory. Probable cause requires even more.
Why does this matter?
A violation of your constitutional rights could mean the police can’t use any evidence against you that they got through the traffic stop.
You probably won’t know whether the officers met their constitutional burden before they pulled you over. That is for an attorney to challenge and a judge to decide.
It is important to understand, however, that there are many valid reasons an officer may have for pulling you over.
In Tennessee, basic traffic offenses are Class C misdemeanors, so the officer needs a reasonable suspicion before pulling you over for one. However, they would only need to observe a misdemeanor traffic infraction to meet their burden.
Sometimes, the police do not meet their constitutional burden. If you end up with a ticket or a criminal charge, the question of whether the officer had a reasonable suspicion may become crucial to your case.
Because the police aren’t allowed to partake in unconstitutional activities, they can’t use any evidence they get by doing so. This is called the “exclusionary rule.” This is what people mean when they say the evidence was “thrown out.”
If a judge throws the evidence out, the prosecutor may no longer have enough evidence to prosecute you, meaning the charges would have to be dismissed.