Final answer:
The exclusionary rule excludes illegally obtained evidence from being used in court, ensuring that individuals' constitutional rights are protected. It was established by landmark Supreme Court cases and includes the doctrine of 'fruit of the poisonous tree.' However, some exceptions to the rule exist, like the 'good faith' and 'inevitable discovery' exceptions.
Step-by-step explanation:
What Does the Exclusionary Rule Exclude?
The exclusionary rule is designed to exclude illegally obtained evidence from being used in court. Specifically, the rule prevents evidence acquired in violation of a person's constitutional rights, particularly the Fourth Amendment, from being introduced in a criminal trial to secure a conviction. This includes evidence obtained without a warrant when a warrant was required, unless an exception to the warrant requirement applies.
Established by the Supreme Court case Mapp v. Ohio in 1961, and first applied on a federal level in 1914 in Weeks v. United States, the exclusionary rule serves to ensure that the government follows the law and respects individuals' constitutional rights. The rule applies not just to the evidence directly seized illegally, but also to any additional evidence derived from the initial illegality, a doctrine known as the "fruit of the poisonous tree."
There are, however, exceptions to the exclusionary rule, such as the "good faith" exception, where police reasonably believe they are acting according to legal authority, and the "inevitable discovery" exception, where evidence would have been found legally regardless of the error.