A court-made rule that blocks prosecutors from using evidence obtained through a violation of a person's constitutional rights, most often an unlawful search, seizure, or interrogation.

Most often, the rule comes up when police gather evidence in a way that breaks the Fourth, Fifth, or Sixth Amendments. If officers search a car without a valid warrant or exception, for example, drugs, weapons, or phone data found in that search may be kept out of court. The same idea can apply to statements taken after an improper custodial interrogation or after denying access to counsel. Courts may also suppress the "fruit of the poisonous tree," meaning later evidence discovered because of the original illegality. There are exceptions, though, including good faith, inevitable discovery, and independent source - because few rules in criminal procedure travel in a perfectly straight line.

In practice, the exclusionary rule can reshape a case. If key evidence is thrown out, charges may be reduced, dismissed, or pushed toward a better plea bargain. For someone facing an injury-related criminal case - such as a DWI crash or vehicular assault allegation - the difference can be huge if blood-test results, body-camera statements, or vehicle-search evidence are suppressed.

In Minnesota, these issues are usually raised through a motion to suppress under the Minnesota Rules of Criminal Procedure. Minnesota courts also apply federal constitutional protections and Article I, Section 10 of the Minnesota Constitution, which can sometimes offer broader search-and-seizure protection than the federal baseline.