For more than 100 years after the ratification of the Fourth Amendment, it was of little value to criminal defendants because evidence seized by law enforcement in violation of warrant or reasonableness requirements was still admissible during the trial of the accused accuses. The United States Supreme Court fundamentally changed Fourth Amendment jurisprudence when it issued its decision in Weeks v. United States. In the landmark case of Weeks v. United States in 1914, the United States Supreme Court announced the far-reaching legal doctrine known today as the exclusionary rule, which generally prohibits the use in court of illegally obtained evidence. In the Weeks case, federal agents kicked in his front door, searched his home without a search warrant, and discovered several incriminating documents, which were later used against him during the federal trial. The Supreme Court said that such evidence must be thrown out because it was obtained illegally. Five decades later, in Mapp v. Ohio (1961), the Court extended the exclusionary rule to criminal trials held at the state level. The Mapp decision ended this federal-state discrepancy, and the courts have declared that the fruits of unconstitutional research are now inadmissible in both state and federal courts. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an original essay There are some exceptions to the exclusion rule, these rules could be for many different reasons but can be used in different ways. A good example is that, under the good faith exception, evidence is not excluded if it is obtained by officers reasonably relying on a search warrant that turns out to be invalid. The independent source doctrine states that evidence initially obtained during an illegal search or seizure may later be admissible if the evidence is subsequently obtained through a constitutionally valid search or seizure. The doctrine of unavoidable discovery is related to the independent source doctrine and allows the admission of evidence discovered in an unlawful search or seizure if it would have been discovered anyway under the same conditions, by an independent line of inquiry that had already been pursued at the time it was discovered. the illicit search or seizure has been verified. The doctrine of mitigation is used in cases where the relationship between the disputed evidence and the unconstitutional conduct is too remote and attenuated, the evidence may be admissible. Evidence admissible for impeachment is the exclusionary rule that does not prevent the government from introducing illegally collected evidence to impeach or attack the credibility of defendants' testimony at trial. The Supreme Court recognized this exception in Harris v. New York as a truth-telling tool to prevent perjury. Even when the government suspects perjury, however, it can only use tainted evidence for impeachment and not use it to prove guilt. The last example is called Qualified Immunity. This exclusionary rule is often the only remedy available to a defendant when police officers conduct an unreasonable search or violate their Miranda rights. Even if officers violate a defendant's constitutional or statutory rights, qualified immunity protects officers from a lawsuit unless no reasonable officer could believe that the officers' conduct was lawful. Please note: this is just an example. Get a custom paper from our expert writers now. Get an essay.