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criminal

Exclusionary Rule

A legal principle that prohibits evidence obtained in violation of the defendant's constitutional rights from being used at trial.

Encyclopedia entry: Exclusionary Rule

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exclusionary rule

Overview

The exclusionary rule prevents the government from using most evidence  gathered in violation of the United States Constitution .  The decision in Mapp v. Ohio  established that the exclusionary rule applies to evidence  gained from an unreasonable search or seizure  in violation of the Fourth Amendment . The decision in Miranda v. Arizona  established that the exclusionary rule applies to improperly elicited self-incriminatory statements gathered in violation of the Fifth Amendment , and to evidence gained in situations where the government violated the defendant's Sixth Amendment  right to counsel .  However, the rule does not apply in civil cases , including deportation hearings . See INS v. Lopez-Mendoza .

Derivatives of Excluded Evidence

If evidence  that falls within the scope of the exclusionary rule led law enforcement to other evidence, which they would not otherwise have located, then the exclusionary rule applies to the newly discovered evidence, subject to a few exceptions. The secondarily excluded evidence is called “fruit of the poisonous tree .”

Though the rationale behind the exclusionary rule is based in constitutional rights, it is a court-created remedy  and deterrent, not an independent constitutional right .  The purpose of the rule is to deter law enforcement officers from conducting searches or seizures  in violation of the Fourth Amendment  and to provide remedies to defendants whose rights  have been infringed.  Courts have also carved out several exceptions to the exclusionary rule where the costs of exclusion outweigh its deterrent or remedial benefits.  For example, the good-faith exception , below, does not trigger the rule because excluding the evidence  would not deter police officers from violating the law in the future.

Exceptions

Good Faith Exception

Under the good-faith exception , evidence is not excluded if it is obtained by officers who reasonably  rely on a search warrant  that turns out to be invalid. See Arizona v. Evans . Also, in Davis v. U.S. , the U.S. Supreme Court  ruled that the exclusionary rule does not apply when the police conduct a search in reliance on binding appellate  precedent  allowing the search. Under Illinois v. Krull , evidence may be admissible  if the officers rely on a statute  that is later invalidated.  In Herring v. U.S. , the Court found that the good-faith exception to the exclusionary rule applies when police employees erred in maintaining records in a warrant  database.

Independent Source Doctrine

Evidence initially obtained during an unlawful search or seizure may later be admissible  if the evidence is later obtained through a constitutionally valid search or seizure. Murray v. U.S.  is the modern interpretation of the independent source doctrine, originally adopted in Nix v. Williams . Additionally, some courts recognize an "expanded" doctrine, in which a partially tainted warrant is upheld if, after excluding the tainted information that led to its issuance, the remaining untainted information establishes probable cause sufficient to justify its issuance. See, for example, the South Dakota Supreme Court decision in State v. Boll .

Inevitable Discovery Doctrine

Related to the independent source doctrine, above, and also adopted in Nix v. Williams , the inevitable discovery doctrine allows admission of evidence that was discovered in an unlawful search or seizure if it would have be discovered in the same condition anyway, by an independent line of investigation that was already being pursued when the unlawful search or seizure occurred.

Attenuation Doctrine

In cases where the relationship between the evidence challenged and the unconstitutional conduct is too remote and attenuated, the evidence may be admissible. See Utah v. Strieff . Brown v. Illinois , cited in Strieff, articulated three factors for the courts to consider when determining attenuation: temporal proximity, the presence of intervening circumstances, and the purpose and flagrancy of the official misconduct.

Evidence Admissible for Impeachment

The exclusionary rule does not prevent the government from introducing illegally gathered 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-testing device to prevent perjury . Even when the government suspects perjury, however, it may only use tainted evidence for impeachment, and may not use it to show guilt.

Qualified Immunity

Due to qualified immunity , the exclusionary rule is often a defendant's only remedy 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 the officers from a lawsuit  unless no reasonable  officer would believe that the officers' conduct was legal. 

In Vega v. Tekoh (2022)  the Supreme Court held that violating Miranda Rights does not provide a basis for a § 1983 claim . Rather, the court asserted that Miranda imposed “a set of prophylactic rules” that only focused on disallowing the use of statements obtained in violation of those rules. Further, the court held that expanding Miranda rights beyond that would impose substantial costs on the judicial system. 

[Last reviewed in November of 2022 by the Wex Definitions Team
]

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This is legal information, not legal advice. Laws vary by jurisdiction and change frequently. Always verify current law with official sources and consult a licensed attorney in your jurisdiction for advice on your specific situation.