347 U.S. 62 (1954)
Walder v. United States is a landmark Supreme Court case that addresses the admissibility of evidence seized in violation of the Fourth Amendment, specifically in the context of using such evidence for impeachment purposes against a defendant who introduces contradictory evidence.
Can evidence obtained through a violation of the Fourth Amendment be used to impeach a defendant's credibility when the defendant testifies contrary to that evidence?
Illegally obtained evidence cannot be used in the prosecution's case-in-chief due to the exclusionary rule, but it may be used for the purpose of impeaching the credibility of the defendant if the defendant introduces contradictory evidence.
The Supreme Court held that the government could use evidence obtained from an unlawful search to impeach a defendant's credibility, even if such evidence could not be used in the main case due to the exclusionary rule.
Walder v. United States is significant for law students as it illustrates the potential limitations and exceptions to the exclusionary rule, a foundational doctrine in criminal procedure that protects constitutional rights. It demonstrates how the Court reconciles competing interests: preventing the government from profiting from illegal searches while maintaining the truthfulness of court proceedings. This case also sets the stage for later developments in the law, influencing decisions about the scope of the exclusionary rule and its impact on the criminal justice system.