The Exclusionary Rule
The constitutional rules that surround the Fourth Amendment are unique. In many cases involving the Bill of Rights, the Court is faced with people who have been prosecuted because they wanted to exercise their constitutional rights. For example, the defendant might be someone who has relied on the right of free speech to make a speech in a public park. In most of these cases, the question for the Court is whether or not the person's actions were protected by the Constitution. If they were, then the person goes free. If they were not, then the person goes to jail. When the Fourth Amendment is involved, however, the situation is very different.
In most cases involving the Fourth Amendment, the defendants have not been prosecuted because they chose to exercise their constitutional rights. Far from it. Instead, the defendants in Fourth Amendment cases are usually people who have violated a section of the criminal code that everyone agrees the state has every right to enforce. For example, the defendants might be convicted murderers, drug smugglers, or robbers.
In Fourth Amendment cases, the police have violated a defendant's rights in the process of arresting him or her. In some of these cases, the police have simply made a constitutional mistake; they could have followed the rules and gotten the necessary evidence without violating anyone's rights. In other cases, however, the Supreme Court is faced with criminals who never would have been caught if the police had not violated the Fourth Amendment.
In addressing the difficult question of what to do when the Fourth Amendment has been violated, the Supreme Court has tried many approaches. The