It has been suggested that this article or section be merged with Exclusionary rule. (Discuss)

Criminal procedure

Investigating and charging crimes

Criminal investigation

Arrest warrant · Search warrant Probable cause Knock-and-announce Exigent circumstance Reasonable suspicion Search and seizure Search of persons Arrest · Detention Right to silence · Miranda warning Grand jury

Criminal prosecution

Statute of limitations · Nolle prosequi Bill of attainder · Ex post facto law Criminal jurisdiction · Extradition Habeas corpus · Bail Inquisitorial system Adversarial system

Charges and pleas

Arraignment · Information Indictment Plea · Peremptory plea Nolo contendere · Plea bargain Presentence Investigation

Related areas

Criminal defenses Criminal law · Evidence Civil procedure

Portals

Law · Criminal justice

v • d • e

Fruit of the poisonous tree is a legal metaphor in the United States used to describe evidence gathered with the aid of information obtained illegally.^[1] The logic of the terminology is that if the source of the evidence (the "tree") is tainted, then anything gained from it (the "fruit") would be likewise.

Such evidence is not generally admissible in court.^[2] For example, if a police officer conducted an unconstitutional (Fourth Amendment) search of a home and obtained a key to a locker in a train station, thus obtaining evidence of a crime from the locker, then that evidence would more than likely be excluded in accordance with the fruit of the poisonous tree doctrine. The discovery of a witness is not evidence in itself, due to the fact that the witness is attenuated by separate interviews, in-court testimony and their own statements.

The doctrine is an extension of the exclusionary rule, which, subject to some exceptions, prevents evidence obtained in violation of the Fourth Amendment from being admitted in a criminal trial. Like the exclusionary rule, the fruit-of-the-poisonous-tree doctrine is intended to deter police from using illegal means to obtain evidence.

The doctrine is subject to three main exceptions. The tainted evidence will be admissible if (1) it was discovered in part as a result of an independent, untainted source; (2) it would inevitably have been discovered despite the tainted source; or (3) the chain of causation between the illegal action and the tainted evidence is too attenuated.

The Fruit of the Poisonous Tree doctrine stems from the 1920 case of Silverthorne Lumber Co. v. United States.^[3]

The Fruit of the Poisonous Tree phrase is a reference to the biblical passage originally found in Matthew 7:17-20.

Notes and references