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The Exclusionary Rule prevents the government from using most evidence gathered in violation of the United States Constitution. It applies to evidence gained from an unreasonable search or seizure in violation of the Fourth Amendment, see Mapp v. Ohio, 367 U.S. 643 (1961), to improperly elicited self-incriminatory statements gathered in violation of the Fifth Amendment, see Miranda v. Arizona, 384 U.S. 439 (1966), and to evidence gained in situations where the government violated defendants’ Sixth Amendment Right to Counsel, see Miranda. The rule does not apply to civil cases, including deportation hearings. See INS v. Lopez-Mendoza, 468 U.S. 1032. The fruit of the poisonous tree is an extension of the exclusionary rule established in Silverthorne Lumber Co. v. United States, 251 U.S. 385 (1920). This doctrine holds that evidence gathered with the assistance of illegally obtained information must be excluded from trial. Thus, if an illegal interrogation leads to the discovery of physical evidence, both the interrogation and the physical evidence may be excluded, the interrogation because of the exclusionary rule, and the physical evidence because it is the “fruit” of the illegal interrogation. This doctrine is subject to three of important exceptions. The evidence will not be excluded (1) if it was discovered from a source independent of the illegal activity; (2) its discovery was inevitable; or (3) if there is attenuation between the illegal activity and the discovery of the evidence.