Final answer:
The Exclusionary Rule is a legal principle that prevents illegally obtained evidence from being used in a criminal trial. It was established through Supreme Court cases like Mapp v. Ohio in 1961. The rule protects individuals from unlawful searches and seizures and safeguards their constitutional rights.
Step-by-step explanation:
The purpose of the Exclusionary Rule is to remove legal evidence from a criminal trial if it was obtained illegally, in violation of the Fourth Amendment. This rule was established through Supreme Court cases like Mapp v. Ohio in 1961 and Weeks v. United States in 1914. If the police conduct an illegal search or seizure without a warrant and find evidence of a crime, that evidence cannot be used in a state criminal trial.
However, there are exceptions to the Exclusionary Rule. If the police executed a warrant they believed was correctly granted but was later found to be incorrect, the evidence obtained may still be admissible under the "good faith" exception. Additionally, the "inevitable discovery" exception allows for the use of evidence that would have been found through legal means anyway, regardless of the illegal search or seizure.
In summary, the purpose of the Exclusionary Rule is to protect individuals from illegal searches and seizures, and it ensures that evidence obtained in violation of the Fourth Amendment cannot be used in a criminal trial.