If the defense can show that the police violated the defendant’s constitutional rights, the evidence the police garnered from the violation is generally not admissible in court. The question of whether your rights were violated is very complex and depends on the exact circumstances. There are basic rules the police have to follow, however.
If you are arrested after a traffic stop, you may not know if your rights were violated. You may need an attorney to advise you and make the appropriate argument to the judge. In other cases, it may be painfully clear. The best way you can assist your defense is to tell your attorney exactly what happened.
Here is a very basic outline of what police are required to do before they pull you over, search you or arrest you. If they have not done what is required, your rights may have been violated and the evidence should be thrown out.
To pull you over, the police need reasonable suspicion of a criminal violation
The police are allowed to run general traffic stops, such as sobriety checkpoints, where people are stopped according to certain rules.
Before the police can pull you over in other contexts, they need, at least, to be able to articulate a reason they suspected criminal activity was taking place.
If you committed a criminal traffic violation and the officer saw it occur, that would very likely count as reasonable suspicion of criminal activity. This is because most Tennessee traffic violations are considered criminal violations.
By contrast, if the officer relied on a hunch or bias alone, pulling you over would violate your Fourth Amendment rights to be free of unreasonable search and seizure. As a result, the evidence would not be admissible in court.
The police need probable cause to search your vehicle – usually
The police are allowed to ask you permission to search your vehicle. If you give permission, the search is considered perfectly legal. However, you don’t have to consent to a search of your vehicle. Simply state, “I do not consent to any searches.” This may be hard to do, but it is within your rights.
The police may sometimes search your vehicle without your consent. If they do, you should not resist.
That is because the police can legally search your car if they have probable cause to believe there is evidence of a crime in your vehicle, or to believe that you are armed and dangerous. They can also legally search your car if they arrest you, or merely if they impound your vehicle. There are many complex rules of when the police can legally search your car.
The police need probable cause to arrest you
Police officers can only arrest you if they have probable cause to believe you have committed a crime. If they do not and the defense can show that, the arrest would violate your rights. Therefore, any evidence garnered from it would be inadmissible.