Silverthorne Lumber Co. v. United States, 251 U.S. 385 (1920), was a U.S. Supreme Court decision in which Silverthorne had attempted to evade paying taxes. Federal agents illegally seized tax books from Silverthorne and created copies of the records. The ruling, delivered by Oliver Wendell Holmes Jr., was that any evidence obtained, even indirectly, from an illegal search was inadmissible in court. He reasoned that otherwise, police would have an incentive to circumvent the Fourth Amendment to obtain derivatives of the illegally obtained evidence.^[1] This precedent later became known as the "fruit of the poisonous tree doctrine,"^[2] and is an extension of the exclusionary rule.

Silverthorne Lumber Co. v. United States
Supreme Court of the United States
Argued December 12, 1919 Decided January 26, 1920
Full case name	Silverthorne Lumber Co., Inc., et al. v. United States
Citations	251 U.S. 385 (more) 40 S. Ct. 182; 64 L. Ed. 319; 1920 U.S. LEXIS 1685
Holding
To permit derivatives would encourage police to circumvent the Fourth Amendment, so the illegal copied evidence was held tainted and inadmissible.
Court membership
Chief Justice Edward D. White Associate Justices Joseph McKenna · Oliver W. Holmes Jr. William R. Day · Willis Van Devanter Mahlon Pitney · James C. McReynolds Louis Brandeis · John H. Clarke
Case opinions
Majority	Holmes, joined by McKenna, Day, Van Devanter, McReynolds, Brandeis, Clark
Dissent	White
Dissent	Pitney

Chief Justice Edward Douglass White and Associate Justice Mahlon Pitney dissented without a written opinion.