Fruit of the poisonous trees is a doctrine that extends the exclusionary rule to make evidence inadmissible in court if it was derived from evidence that was illegally obtained. As the metaphor suggests, if the evidential "tree" is tainted, so is its "fruit." The doctrine was established in 1920 by the decision in Silverthorne Lumber Co. v. United States, and the phrase "fruit of the poisonous tree" was coined by Justice Frankfurter in his 1939 opinion in Nardone v. United States. The rule typically bars even testimonial evidence resulting from excludable evidence, such as a confession.
Like the exclusionary rule itself, this doctrine is subject to three important exceptions. The evidence will not be excluded:
- if it was discovered from a source independent of the illegal activity;
- its discovery was inevitable;
- or for evidence found as a result of excludable, voluntary testimony from the defendant.
Further, if the primary evidence was illegally obtained, but admissible under the good faith exception, its derivatives (or "fruit") may also be admissible.
[Last updated in December of 2022 by the Wex Definitions Team]