747 Opinion of the Court. ing trial, with one Chin Poy. The circumstances are these: Petitioner, On Lee, had a laundry in Hoboken. A customers' room opened on the street, back of it was a room for ironing tables, and in the rear were his living quarters. Chin Poy, an old acquaintance and former employee, sauntered in and, while customers came and went, engaged the accused in conversation in the course of which petitioner made incriminating statements. He did not know that Chin Poy was what the Government calls "an undercover agent" and what petitioner calls a "stool pigeon" for the Bureau of Narcotics. Neither did he know that Chin Poy was wired for sound, with a small microphone in his inside overcoat pocket and a small antenna running along his arm. Unbeknownst to petitioner, an agent of the Narcotics Bureau named Lawrence Lee had stationed himself outside with a receiving set properly tuned to pick up any sounds the Chin Poy microphone transmitted. Through the large front window Chin Poy could be seen and through the receiving set his conversation, in Chinese, with petitioner could be heard by agent Lee. A few days later, on the sidewalks of New York, another conversation took place between the two, and damaging admissions were again "audited" by agent Lee. For reasons left to our imagination, Chin Poy was not called to testify about petitioner's incriminating admissions. Against objection, however, agent Lee was al 3 It seems probable that petitioner failed to properly object to agent Lee's testimony. Shortly after agent Lee began to testify, petitioner's counsel addressed the court: ". . . I would like to enter a general objection to testimony by this witness of conversations alleged to have been had between Agent Gim and Gong not in the hearing of the defendant on trial or in his presence." This objection is not even addressed to the testimony describing the conversation between On Lee and Chin Poy. Later, when agent Opinion of the Court. 343 U.S. lowed to relate the conversations as heard with aid of his receiving set. Of this testimony, it is enough to say that it was certainly prejudicial if its admission was improper. Petitioner contends that this evidence should have been excluded because the manner in which it was ob Lee started to describe the conversation between On Lee and Chin Poy, petitioner's counsel said, "That is objected to." At best this is a general objection which is insufficient to preserve such a specific claim as violation of a constitutional provision in obtaining the evidence. Wigmore on Evidence, § 18 (C) (1). Some jurisdictions recognize an exception to the rule that an overruled general objection cannot avail proponent on appeal in the case where it appears on the face of the evidence that it is admissible for no purpose whatever, or where the nature of the precise specific objection which could be made is readily discernible. Sparks v. Territory of Oklahoma, 146 F. 371. But this exception is generally confined to the cases where such evidence was plainly irrelevant. Where, as in this case, the objection relies on collateral matter to show inadmissibility, and in addition the exclusionary rule to be relied on involves interpretation of the Constitution, the orthodox rule of evidence requiring specification of the objection is buttressed by the uniform policy requiring constitutional questions to be raised at the earliest possible stage in the litigation. To call the objection a general one is to put it in the light most favorable to petitioner; later colloquy between counsel and court indicates that the intended ground of that objection was irrelevance. There were in addition motions to dismiss the indictment on each count, and to exclude certain other testimony, but no reference to the testimony here in question at the motion stage. There was no motion for a new trial, but there was a motion to set aside the verdict-but still no mention of the search-and-seizure argument for exclusion. There is not even any mention of it in the statement of points to be relied on in the Court of Appeals. The Court of Appeals, however, does treat it fully, presumably under Rule 52 (b) of the Rules of Criminal Procedure, allowing the appellate court to notice "plain error." Though we think the Court of Appeals would have been within its discretion in refusing to consider the point, their having passed on it leads us to treat the merits also. 747 Opinion of the Court. 5 tained violates both the search-and-seizure provisions of the Fourth Amendment, and § 605 of the Federal Communications Act (47 U. S. C. § 605); and, if not rejected on those grounds, we should pronounce it inadmissible anyway under the judicial power to require fair play in federal law enforcement. The conduct of Chin Poy and agent Lee did not amount to an unlawful search and seizure such as is proscribed by the Fourth Amendment. In Goldman v. United States, 316 U. S. 129, we held that the action of federal agents in placing a detectaphone on the outer wall of defendant's hotel room, and thereby overhearing conversations held within the room, did not violate the Fourth Amendment. There the agents had earlier committed a trespass in order to install a listening device within the room itself. Since the device failed to work, the Court expressly reserved decision as to the effect on the search-and-seizure question of a trespass in that situation. Petitioner in the instant case has seized upon that dictum, apparently on the assumption that the presence of a radio set would automatically bring him within the reservation if he can show a trespass. But petitioner cannot raise the undecided question, for here no trespass was committed. Chin Poy entered a place of business with the consent, if not by the implied "The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized." U. S. Const., Amend. IV. 5". . . no person not being authorized by the sender shall intercept any communication and divulge or publish the existence, contents, substance, purport, effect, or meaning of such intercepted communication to any person Opinion of the Court. 343 U.S. invitation, of the petitioner. Petitioner contends, however, that Chin Poy's subsequent "unlawful conduct" vitiated the consent and rendered his entry a trespass ab initio. If we were to assume that Chin Poy's conduct was unlawful and consider this argument as an original proposition, it is doubtful that the niceties of tort law initiated almost two and a half centuries ago by the case of the Six Carpenters, 8 Coke 146 (a), cited by petitioner, are of much aid in determining rights under the Fourth Amendment. But petitioner's argument comes a quarter of a century too late: this contention was decided adversely to him in McGuire v. United States, 273 U. S. 95, 98, 100, where Mr. Justice Stone, speaking for a unanimous Court, said of the doctrine of trespass ab initio: "This fiction, obviously invoked in support of a policy of penalizing the unauthorized acts of those who had entered under authority of law, has only been applied as a rule of liability in civil actions against them. Its extension is not favored." He concluded that the Court would not resort to "a fiction whose origin, history, and purpose do not justify its application where the right of the government to make use of evidence is involved." This was followed in Zap v. United States, 328 U. S. 624, 629. By the same token, the claim that Chin Poy's entrance was a trespass because consent to his entry was obtained by fraud must be rejected. Whether an entry such as this, without any affirmative misrepresentation, would be a trespass under orthodox tort law is not at all clear. See Prosser on Torts, § 18. But the rationale of the McGuire case rejects such fine-spun doctrines for exclusion of evidence. The further contention of petitioner that agent Lee, outside the laundry, was a trespasser because by these aids he overheard what went on inside verges on the frivolous. Only in the case of physical entry, either 747 Opinion of the Court. by force, as in McDonald v. United States, 335 U. S. 451, by unwilling submission to authority, as in Johnson v. United States, 333 U. S. 10, or without any express or implied consent, as in Nueslein v. District of Columbia, 73 App. D. C. 85, 115 F. 2d 690, would the problem left undecided in the Goldman case be before the Court. Petitioner relies on cases relating to the more common and clearly distinguishable problems raised where tangible property is unlawfully seized. Such unlawful seizure may violate the Fourth Amendment, even though the entry itself was by subterfuge or fraud rather than force. United States v. Jeffers, 342 U. S. 48; Gouled v. United States, 255 U. S. 298 (the authority of the latter case is sharply limited by Olmstead v. United States, 277 U. S. 438, at 463). But such decisions are inapposite in the field of mechanical or electronic devices designed to overhear or intercept conversation, at least where access to the listening post was not obtained by illegal methods. Petitioner urges that if his claim of unlawful search and seizure cannot be sustained on authority, we reconsider the question of Fourth Amendment rights in the field of overheard or intercepted conversations. This apparently is upon the theory that since there was a radio set involved, he could succeed if he could persuade the Court to overturn the leading case holding wiretapping to be outside the ban of the Fourth Amendment, Olmstead v. United States, 277 U. S. 438, and the cases which have followed it. We need not consider this, however, for success in this attempt, which failed in Goldman v. United States, 316 U. S. 129, would be of no aid to petitioner unless he can show that his situation should be treated as wiretapping. The presence of a radio set is not sufficient to suggest more than the most attenuated analogy to wiretapping. Petitioner was talking confidentially and indiscreetly with one he trusted, and he |