347 U.S. 62 (1954)
In May 1950, petitioner was indicted in the United States District Court for the Western District of Missouri for purchasing and possessing one grain of heroin.1 Claiming that the heroin capsule had been obtained through an unlawful search and seizure, petitioner moved to suppress it. The motion was granted, and shortly thereafter, on the Government’s motion, the case against petitioner was dismissed.2
In January of 1952, petitioner was again indicted, this time for four other illicit transactions in narcotics. The Government’s case consisted principally of the testimony of two drug addicts who claimed to have procured the illicit stuff from petitioner under the direction of federal agents. The only witness for the defense was the defendant himself, petitioner here. He denied any narcotics dealings with the two Government informers and attributed the testimony against him to personal hostility.3
Early on his direct examination petitioner testified that he had never sold any narcotics to anyone in his life.4 When asked if he had ever had any narcotics in his possession other than what may have been given to him by a physician for an ailment, he answered "No."5 When asked if he had ever handed or given any narcotics to anyone as a gift or in any other manner, he answered "I have not."6 When asked if he had ever acted as a conduit for the purpose of handling what he knew to be a narcotic from one person to another, he answered "No, sir."7 On cross-examination, in response to a question by Government counsel making reference to this direct testimony, petitioner reiterated his assertion that he had never purchased, sold or possessed any narcotics. Over the defendant’s objection, the Government then questioned him about the heroin capsule unlawfully seized from his home in his presence back in February 1950. The defendant stoutly denied that any narcotics were taken from him at that time.8
The Government then put on the stand one of the officers who had participated in the unlawful search and seizure and also the chemist who had analyzed the heroin capsule there seized. The trial judge admitted this evidence, but carefully charged the jury that it was not to be used to determine whether the defendant had committed the crimes here charged, but solely for the purpose of impeaching the defendant’s credibility. The defendant was convicted, and the Court of Appeals for the Eighth Circuit affirmed, one judge dissenting.9 The Supreme Court granted certiorari.10
Whether the defendant’s assertion on direct examination that he had never possessed any narcotics opened the door, solely for the purpose of attacking the defendant’s credibility, to evidence of the heroin unlawfully seized in connection with the earlier proceeding?11
The Fourth Amendment provides that the right of the people to be secure in their persons, houses, papers, and effects against unreasonable searches and seizures shall not be violated. The Government cannot violate the Fourth Amendment through its agents and use the fruits of such unlawful conduct to secure a conviction.12 The exclusionary rule announced in Weeks v. United States bars the government from using the fruits of an unlawful search to secure a conviction.13 Nor can the Government make indirect use of such evidence for its case.14 It may not support a conviction on evidence obtained through leads from the unlawfully obtained evidence.15 All these methods are outlawed, and convictions obtained by means of them are invalidated, because they encourage the kind of society that is obnoxious to free men.16 It is one thing to say that the Government cannot make an affirmative use of evidence unlawfully obtained.17 It is quite another to say that the defendant can turn the illegal method by which evidence in the Government’s possession was obtained to his own advantage, and provide himself with a shield against contradiction of his untruths.18 Such an extension of the Weeks doctrine would be a perversion of the Fourth Amendment.19 The Constitution guarantees a defendant the fullest opportunity to meet the accusation against him.20 He must be free to deny all the elements of the case against him without thereby giving leave to the Government to introduce by way of rebuttal evidence illegally secured by it, and therefore not available for its case in chief.21 Beyond that, however, there is hardly justification for letting the defendant affirmatively resort to perjurious testimony in reliance on the Government’s disability to challenge his credibility.22
Yes. The rule distinguishes between affirmative use of unlawfully seized evidence in the government’s case in chief and limited use of that evidence to impeach a defendant who has made sweeping claims on direct examination.23 In the present case the government’s case in chief consisted principally of the testimony of two drug addicts who claimed to have procured the illicit stuff from the petitioner under the direction of federal agents.24 Only after the petitioner took the stand and testified that he had never sold any narcotics to anyone in his life did the government cross-examine him about the heroin capsule unlawfully seized from his home in February 1950.25 When asked if he had ever had any narcotics in his possession other than what may have been given to him by a physician for an ailment, he answered "No." When asked if he had ever handed or given any narcotics to anyone as a gift or in any other manner, he answered "I have not." When asked if he had ever acted as a conduit for the purpose of handling what he knew to be a narcotic from one person to another, he answered "No, sir."
The trial judge admitted the testimony of the participating officer and the chemist but carefully charged the jury that the evidence was not to be used to determine whether the defendant had committed the crimes charged in the January 1952 indictment but solely for the purpose of impeaching the defendant’s credibility.26 This limited impeachment use does not violate the Weeks doctrine because the petitioner went beyond a mere denial of complicity in the crimes charged and made the sweeping claim that he had never dealt in or possessed any narcotics.27 The situation is sharply contrasted with Agnello v. United States where the defendant was not asked and did not testify concerning the can of cocaine on direct examination.28