Unfortunately, this rule only applied to the Federal government in earlier times. But that all changed in 1961, with the case of Mapp vs. Ohio. Dollree Mapp was a Cleveland woman who came under police suspicion for illegal gambling activities. So having probable cause, the local police broke into her home looking for evidence. But while they were there, the police came across a cache of obscene materials, which were outlawed at that time. Mapp was then convicted for the possession of them. But she felt that the exclusionary rule should be made part of the 4th Amendment, and appealed to the federal courts. She claimed that because the police were looking specifically for gambling material, their warrant did not cover the evidence that they had charged her for possessing. In a landmark case, the Supreme Court reversed the decision in Mapp's favor, and since then the exclusionary rule has been incorporated into the 4th Amendment to limit not only the Federal government, but the States as well.
Although the exclusionary rule has been used to protect citizens from illegal search and seizure, there have been specific examples in the past where the Supreme Court has overturned appeals claiming that the prosecution had introduced tainted evidence. In United States vs. Leon, the Supreme Court established the good-faith exception to the rule. This stated that evidence could be used if the police who obtained it thought they were operating under a constitutionally legal search warrant. Another example of these exceptions is the allowing of illegally seized evidence only if the evidence led police to a discovery that they could have made without it. These exceptions to the rule are not meant to take away the right of the citizen, but are just a more conservative spin on the rule incorporated into the 4th Amendment.
As you can see from the above examples, conservatives want the Bill of Rights to have special exceptions for certain circumstances.
