dissenting.
I cannot agree with the majority that the Constitution permits the Government to enforce the summons issued in this case. The opinion of the Court fails to articulate the basis of its result in a way that addresses the range of constitutional concerns involved.1 The majority seems to create a bright-line rule that no constitutional right of petitioner is violated by enforcing a summons of papers not in her possession. Like Mr. Justice Brennan, I could not accept such a rule. However, the majority blurs the line by suggesting that temporary relinquishment of possession presents a different case, see ante, at 333. The Court expressly disclaims the proposition that possession alone is determinative of the availability of constitutional protection for petitioner’s papers. Ante, at 336, and 333 n. 16. But neither the opinion of the Court nor the concurring opinion of Mr. Justice Brennan supplies a clearly articulated constitutional basis for the rule adopted. If the considerations that underlie the Court’s expressed concerns are stated explicitly, I think it is clear that the Court has failed to apply correctly the standards which *345it appears to find relevant.2 I agree, of course, that possession does not define the limits of the protection that the Constitution affords to private papers, and add these comments to indicate how I would treat claims like petitioner's.
A. I begin with Boyd v. United States, 116 U. S. 616 (1886), whose continuing vitality is indicated by the majority’s effort to distinguish it. That was a suit for the forfeiture of 35 cases of plate glass alleged to have been illegally imported. In the course of the forfeiture proceeding, the Government introduced into evidence an invoice of a prior shipment. The defendants objected on the ground that the use of the invoice violated their rights under the Fourth and Fifth Amendments, because the invoice was a private paper secured by a subpoena. This Court found a violation of both amendments.
One might interpret Boyd as holding that the Fifth Amendment prohibits the use of private papers in a criminal proceeding over the author’s objection. The words of the Fifth Amendment surely can be read in that way. The use of the papers over objection “compel [s the author] in .[a] criminal case to be a witness against himself.” The compulsion occurs when the paper is introduced over objection, not when the paper is written or subpoenaed.
*346But that interpretation has not been adopted by this Court. See, e. g., Perlman v. United States, 247 U. S. 7 (1918); Johnson v. United States, 228 U. S. 457 (1913). And in some possible cases, consistent application of that interpretation of Boyd might lead to results at odds with common sense.3
Another interpretation of Boyd has been accepted by this Court and by the leading commentators. See, e. g., Curcio v. United States, 354 U. S. 118, 125 (1957); 8 J. Wigmore, Evidence § 2264 (McNaughton rev. 1961); C. McCormick, Evidence §§ 126-127 (2d ed. 1972). When a party produces potentially incriminating evidence in response to a summons or subpoena, he implicitly testifies that the evidence he brings forth is in fact the evidence demanded. “The custodian’s act of producing books or records in response to a subpoena duces tecum *347is itself a representation that the documents produced are those demanded by the subpoena. Requiring the custodian to identify or authenticate the documents for admission in evidence merely makes explicit what is implicit in the production itself.” Curcio v. United States, 354 U. S., at 125.
The potential for incrimination inherent in the act of production is illustrated by this case. The summons here called for the production of “[a] 11 books .. . pertaining to the tax liability of” petitioner. Had the summons been directed to her, she would have implicitly testified, on producing some papers, that these were “all” the records sought. The Internal Revenue agents believed that she may have understated her income. Their belief might have been confirmed on examining all of .her records, but not on examining only some of them. The records could then be used in a subsequent criminal prosecution for underreporting her income. If she produced only some of her books, though, she would be liable for contempt of the order. The Fifth Amendment was designed to prevent the Government from placing potential defendants in such a position. Cf. Murphy v. Waterfront Comm’n, 378 U. S. 52, 55 (1964).
These considerations operate only against the person in possession of the papers, as the majority correctly points out. In this ease, the accountant to whom the summons was directed made no claim that turning over the records he has might incriminate him, for example, by exposing him to the charge that he had perjured himself in representing that the return prepared for petitioner was correct to the best of his knowledge and belief, 26 U. S. C. § 6065, or that he had knowingly aided in the preparation of a false return, 26 U. S. C. § 7206 (2). Nor could he be held to have represented more than that he had produced all the records in his possession.
*348However, the accepted interpretation of Boyd has an odd sound to it. Boyd emphasized that the invoice there was a private paper written by the defendants. Yet the accepted interpretation of the case makes the authorship and contents of the paper largely irrelevant. What is incriminating about the production of a document in response to an order is not its contents, as one might have thought, but the implicit authentication that the document is the one named in the order.4 If that is the only way rationally to interpret Boyd, it might make sense to do so.5 But it makes better sense to devise a rationale that focuses on the obvious concern of the case, the desire of the author of documents to keep them private.
B. This Court also held in Boyd that the Fourth Amendment was violated. Indeed, much of the opinion is devoted to a discussion of Entick v. Carrington, 19 How. St. Tr. 1029, 95 Eng. Rep. 807 (1765), a landmark in the development of the prohibition against unreasonable searches and seizures. Here, too, the doctrinal basis of the holding is unclear, in part because the Court *349correctly perceived that “[i]n this regard the Fourth and Fifth Amendments run almost into each other.” 116 U. S., at 630.
Boyd suggested that the Fourth Amendment prohibited the seizure of “mere evidence.” 116 U. S., at 623-624. See Gouled v. United States, 255 U. S. 298 (1921). Searches for mere evidence were unreasonable even if such searches were sure to produce evidence leading to a conviction. The precise contours of the “mere evidence” rule were shaped by concepts of property law which we now see as outmoded. See Warden v. Hayden, 387 U. S. 294, 303-307 (1967). But those concepts attempted to define, however imprecisely, a sphere of personal privacy that the Government could not enter over objection. See, e. g., Gouled v. United States, supra, at 304. And when this Court repudiated the “mere evidence” rule, it suggested that Fourth Amendment limitations might be devised precisely in terms of the interest in privacy, prohibiting the seizure of “items of evidential value whose very nature precludes them from being the object of a reasonable search and seizure.” Warden v. Hayden, 387 U. S., at 303. Cf. Stanford v. Texas, 379 U. S. 476, 485 (1965).
The Fourth and Fifth Amendments do not speak to totally unrelated concerns. Cf. Griswold v. Connecticut, 381 U. S. 479, 484-485 (1965); Murphy v. Waterfront Comm’n, 378 U. S., at 55. Both involve aspects of a person’s right to develop for himself a sphere of personal privacy. Where the Amendments “run almost into each other,” I would prohibit the Government from entering.6 The problem, as I see it, is to develop criteria *350for determining whether evidence sought by the Government lies within the sphere of activities that petitioner attempted to keep private. Cf. Katz v. United States, 389 U. S. 347, 351-352 (1967).
The first criterion, as Hayden suggests, is the nature of the evidence. Diaries and personal letters that record only their author’s personal thoughts lie at the heart of our sense of privacy. In contrast, I see no bar in the Fourth or Fifth Amendment to the seizure of a letter from one conspirator to another directing the recipient to take steps that further the conspiracy. Business records like those sought in this case lie between those cases. We are not so outraged by the intrusion on privacy that accompanies the seizure of these records as we are by the seizure of a diary, yet the records could not easily be called “instrumentalities” of tax evasion, particularly if they are accurate.
Second, we must consider the ordinary operations of the person to whom the records are given. A transfer to a lawyer is protected, not simply because there is a recognized attorney-client privilege, but also because the ordinary expectation is that the lawyer will not further publicize what he has been given. Again in contrast, a transfer to a trustee in bankruptcy or to a clerk of a court does not usually carry with it such expectations. That is how I would justify Johnson and Perlman. Here, too, the transfer in this case lies between the extremes. It would be relevant to a decision about the expectation of privacy that an accountant-client priv*351ilege existed under local law, but not determinative. Petitioner disclaimed reliance on such a privilege. Tr. of Oral Arg. 7. But I would think that, privileged or not, a disclosure to an accountant is rather close to disclosure to an attorney.
Third, the purposes for which the records were transferred is an element of an informed judgment about the author’s interest in the privacy of the papers. That a transfer is compelled by practical considerations if the author is to claim benefits available under the law, seems to me quite important. If petitioner had sought to take advantage of some complicated provision of the tax laws, and needed the help of an accountant to do so, I would be quite reluctant to hold that the transfer of her records was a surrender of the privacy of the papers. But cf. Johnson v. United States, 228 U. S. 457 (1913). As I understand it, the majority’s exception for temporary relinquishment of possession, and several of Mr. Justice Brennan’s exceptions, recognize the importance of this criterion.
Finally, we must take into account the steps that the author took to insure the privacy of the records. Cf. In re Harris, 221 U. S. 274, 280 (1911). Placing them in a safe deposit box is different from letting them remain for many years with an accountant.
It is not impossible that petitioner had indeed abandoned her claim to privacy in the papers sought by summons in this case. But the District Court and the Court of Appeals applied a rather rigid test which made possession alone conclusive. Those courts have more experience than we do with the ordinary practices of taxpayers, accountants, and Internal Revenue agents. They are therefore better able, in the first instance, to apply the criteria I believe are relevant, in light of their understanding of the ordinary practices in such cases. I would vacate the judgment and remand the case to the District Court for consideration of those criteria.
In part this results from the conflation of petitioner’s claims under the Fourth and Fifth Amendments. See ante, at 325-326, n. 6. But the constitutional claims are complicated, and their articulation is difficult. The opinion of the Court does not, I believe, present an acceptable rationale for its holding.
It may be that everything in this opinion is implicit in the opinion of the Court. The majority recognizes the importance of the purposes of the transfer, ante, at 334, the steps taken to protect the privacy of the records, ibid., and the ordinary operations of the recipient, ibid. I would be pleased to discover that we had no serious disagreements about the guiding principles in this case, but only a relatively minor disagreement about its proper disposition.
For example, suppose a noted criminal lawyer walked into a police station and presented the desk sergeant with his handwritten confession to the arson of his neighbor's house. Boyd v. United States, 116 U. S. 616 (1886), read as suggested in the text, would bar the use of that document if, at trial, the defendant objected.
That case might be analyzed as a problem of waiver: did the manner in which the author revealed the paper indicate a knowing decision to surrender his rights? The cases that stand in the way of the simplest interpretation of Boyd might be treated similarly. But the “waiver” in those cases was not a waiver in the ordinary sense. In Johnson, for example, the defendant had been indicted for concealing money from his trustee in bankruptcy. The Bankruptcy Act required that he turn over his books to the trustee, and the books were used against Johnson in the criminal case. The transfer of the books was required if Johnson was to have the benefits of bankruptcy available to him. To make that transfer a waiver of Fifth Amendment rights would be to impose an unconstitutional condition.
Still, even if “waiver” is an inappropriate term here, the underlying notion that someone may behave in a way that indicates a relinquishment of his constitutional rights is sound. I rely on it as the proper term to use in analyzing claims like petitioner’s. See infra, at 350.
Another way of seeing the oddity of this interpretation is to consider whether the person who produces documents other than those called for has committed perjury. Perhaps he has, but the perjury is an unusual one. Yet perjury is the third hom of the "cruel trilemma” that the Fifth Amendment was designed to eliminate.
Another interpretation of Boyd makes ownership crucial. A person who owns something has the right to exercise a great deal of control over it. When the Government seizes it, the owner is compelled to give up that right. This interpretation is consistent with the observation in Boyd that contraband and instrumentalities of crime can be seized because the Government has a superior property right in them. However, this interpretation runs into the same difficulties as the accepted one; in particular, it makes the authorship and content of the property irrelevant. And the emphasis on property rights in this area has since been abandoned. See, e. g., Warden v. Hayden, 387 U. S. 294 (1967).
I recognize that there is an alternate view, that unless a Fifth Amendment privilege is involved, the Fourth Amendment authorizes intrusion when it is not unreasonable. However, this Court has held that increasingly severe standards of probable cause are necessary to justify increasingly intrusive searches. Cf. Camara v. *350Municipal Court, 387 U. S. 523 (2967); Terry v. Ohio, 392 U. S. 1 (1968); Stanford v. Texas, 379 U. S. 476 (1965). The precise elements required of a Fifth Amendment violation need not coincide exactly with the elements of an invasion of privacy that should be considered unreasonable, and I see no reason to confine the sphere of privacy free from intrusion to just what the Fifth Amendment protects.