Mr. Chief Justice Vinson
delivered the opinion of the Court.
Petitioner was tried on charges of having made tie-in sales in violation of regulations under the Emergency Price Control Act.1 A plea in bar, claiming immunity from prosecution based on § 202 (g) 2 of the Act, was [4]*4overruled by the trial judge; judgment of conviction followed and was affirmed on appeal. 159 F. 2d 890. A contrary conclusion was reached by the district judge in United States v. Hoffman, post, p. 77. Because this conflict involves an important question of statutory construction, these cases were brought here and heard together. Additional minor considerations involved in the Hoffman case are dealt with in a separate opinion.
The petitioner, a wholesaler of fruit and produce, on September 29, 1944, was served with a subpoena duces tecum and ad testificandum, issued by the Price Administrator under authority of the Emergency Price Control Act. The subpoena directed petitioner to appear before designated enforcement attorneys of the Office of Price Administration and to produce “all duplicate sales invoices, sales books, ledgers, inventory records, contracts and records relating to the sale of all commodities from September 1, 1944 to September 28, 1944.” In compliance with the subpoena, petitioner appeared and, after being sworn, was requested to turn over the subpoenaed records. Petitioner’s counsel inquired whether petitioner was being granted immunity “as to any and all matters for information obtained as a result of the investigation and examination of these records.” The presiding official stated that the “witness is entitled to whatever immunity which flows as a matter of law from the production of these books and records which are required to be kept [5]*5pursuant to MPRs 271 and 426.”3 Petitioner thereupon produced the records, but claimed constitutional privilege.
The plea in bar alleged that the name of the purchaser in the transactions involved in the information appeared in the subpoenaed sales invoices and other similar documents. And it was alleged that the Office of Price Administration had used the name and other unspecified leads obtained from these documents to search out evidence of the violations, which had occurred in the preceding year.
The Circuit Court of Appeals ruled that the records which petitioner was compelled to produce were records required to be kept by a valid regulation under the Price Control Act; that thereby they became public documents, as to which no constitutional privilege against self-incrimination attaches; that accordingly the immunity of § 202 (g) did not extend to the production of these records and the plea in bar was properly overruled by the trial court. 159 F. 2d 890.
It should be observed at the outset that the decision in the instant case turns on the construction of a com[6]*6pulsory testimony-immunity provision which incorporates by reference the Compulsory Testimony Act of 1893. This provision, in conjunction with broad record-keeping requirements, has been included not merely in a temporary wartime measure but also, in substantially the same terms, in virtually all of the major regulatory enactments of the Federal Government.4
[7]*7It is contended that a broader construction of the scope of the immunity provision than that approved by the Circuit Court of Appeals would be more consistent with the congressional aim, in conferring investigatory powers upon the Administrator, to secure prompt disclosure of books and records of the private enterprises subjected to OPA regulations. In support of this contention, it is urged that the language and legislative history of the Act indicate nothing more than that § 202 was included for the purpose of “obtaining information” and that nothing in that history throws any light upon the scope of the immunity afforded by subsection (g). We cannot agree with these contentions. For, the language of the statute and its legislative history, viewed against the background of settled judicial construction of the immunity provision, indicate that Congress required records to be kept as a means of enforcing the statute and did not intend to frustrate the use of those records for enforcement action by granting an immunity bonus to individuals compelled to disclose their required records to the Administrator.
[8]*8The very language of § 202 (a) discloses that the record-keeping and inspection requirements were designed not merely to “obtain information” for assistance in prescribing regulations or orders under the statute, but also to aid “in the administration and enforcement of this Act and regulations, orders, and price schedules thereunder.” 5
The legislative history of § 202 casts even stronger light on the meaning of the words used in that section. On July 30, 1941, the President of the United States, in a message to Congress, requested price-control legislation conferring effective authority to curb evasion and bootlegging.6 Two days later the Price Control Bill was introduced in the House by Representative Steagall, and referred to the Committee on Banking and Currency.
As introduced, and as reported out of the Committee on November 7, 1941, the bill included broad investigatory, record-keeping, licensing, and other enforcement powers to be exercised by the Administrator.7 While it [9]*9was before the House, Representative Wolcott on November 28, 1941, offered as a substitute for § 201 a series of [10]*10amendments, one of which authorized the Administrator “to subpena documents and witnesses for the purpose of obtaining information in respect to the establishment of price ceilings, and a review of price ceilings.”8 This amendment was adopted. Thereupon Representative Wolcott moved to strike out as “redundant” the much broader and far more rigorous provisions in the bill (§ 202), which authorized the Administrator to “require the making and keeping of records and other documents and the making of reports,” and to “obtain or require the furnishing of such information under oath or affirmation or otherwise, as he deems necessary or proper to assist him in prescribing any regulation or order under this act, and in the administration and enforcement of this act, and regulations and orders thereunder.”9 This amendment too was accepted by the House.10
It is significant to note that the Senate Committee on Banking and Currency began its consideration of the [11]*11bill on December 9, 1941, the day after Congress declared the existence of a state of war between this country and the Imperial Government of Japan. Appearing before the Senate Committee in this wartime setting, the proponents of the original measure requested and secured the restoration of the enforcement powers which the House had stricken.11 They asserted that a major aspect of the investigatory powers contained in the bill as originally drafted was to enable the Administrator to ferret out violations and enforce the law against the violators.12 And it was pointed out that in striking down the authority originally given the Administrator in the committee bill to require the maintenance of records, the House had substantially stripped him of his investigatory and enforcement powers,
“because no investigatory power can be effective without the right to insist upon the maintenance of records. By the simple device of failing to keep records of pertinent transactions, or by destroying or falsifying such records, a person may violate the act with impunity and little fear of detection. Especially is this true in the case of price-control legislation, which operates on many diverse industries and commodities, each industry having its own trade practices and methods of operation.
[12]*12“The House bill also deprives the Administrator of the power to require reports and to make inspections and to copy documents. By this deprivation the Administrator’s supervision over the operation of the act is rendered most difficult. He has no expeditious way of checking on compliance. He is left without ready power to discover violations.
“It should not be forgotten that the statute to be administered is an emergency statute. To put teeth into the Price Control Act, it is imperative that the Administrator’s investigatory powers be strong, clear, and well adapted to the objective. . . .”13
Emphasis was placed on the restoration of licensing provisions, which the House had deleted from the Price Control Bill as originally drafted. The General Counsel for the OPA contended that licensing was the backbone of enforcement of price schedules and regulations.14 The [13]*13World War I prototype of the Price Control Act, the Lever Act, had contained authority for the President to license the distribution of any necessaries whenever deemed essential “in order to carry into effect any of the purposes of this Act . . . .”15 It was pointed out that “The general licensing regulations prescribed under the Lever Act, applicable to all licensees, required the making of reports (rule 1), the permitting of inspection (rule 2), and the keeping of records (rule 3).” 16 And it was noted that licensing had been employed in connection with the fuel provisions of the Act “as a method of obtaining information, of insuring universal compliance, and of enforcing refunds of overcharges and the payment of penalty charges to war charities.”17 By li[14]*14censing middlemen, “Violations were readily discovered by examination of the records which each licensee was required to submit.” 18
With this background,19 Congress restored licensing powers to the Administrator in the Price Control Bill as [15]*15enacted, § 205, 50 U. S. C. App. § 925 (f), and provided for the suspension by court action of the license of any person found to have violated any of the provisions of the license or price schedules or other requirements. Non-retail fruit dealers, including petitioner in the present case, were licensed under § 9a of Maximum Price Regulation No. 426, 8 F. R. 16411 (1943).
It is difficult to believe that Congress, whose attention was invited by the proponents of the Price Control Act to the vital importance of the licensing, record-keeping and inspection provisions in aiding effective enforcement of the Lever Act, could possibly have intended § 202 (g) to proffer a “gratuity to crime” by granting immunity to custodians of non-privileged records. Nor is it easy to conceive that Congress could have intended private privilege to attach to records whose keeping it authorized the Administrator to require on the express supposition that it was thereby inserting “teeth” into the Price Control Act since the Administrator, by the use of such records, could readily discover violations, check on compliance, and prevent violations from being committed “with impunity.”
In conformance with these views, the bill as passed by Congress empowered the Administrator to require the making and keeping of records by all persons subject to the statute, and to compel, by legal process, oral testimony of witnesses and the production of documents deemed necessary in the administration and enforcement of the statute and regulations. It also included the immunity proviso, subsection (g) of § 202, as to which no special attention seems to have been paid in the debates, although it was undoubtedly included, as it had been in other statutes, as a “usual administrative provision,” 20 intended to fulfill the purpose customarily fulfilled by such a provision.
[16]*16The inescapable implications of the legislative history related above concerning the other subsections of § 202 would appear to be that Congress did not intend the scope of the statutory immunity to be so broad as to confer a bonus for the production of information otherwise obtainable.
Moreover, there is a presumption that Congress, in reenacting the immunity provision of the 1893 Act, was aware of the settled judicial construction-of the statutory immunity. In adopting the language used in the earlier act, Congress “must be considered to have adopted also the construction given by this Court to such language, and made it a part of the enactment.” 21 That judicial construction is made up of the doctrines enunciated by this Court in spelling out the non-privileged status of records validly required by law to be kept, in Wilson v. United States, 221 U. S. 361 (1911), and the inapplicability of immunity provisions to non-privileged documents, in Heike v. United States, 227 U. S. 131 (1913).
In the former case, Wilson, the president of a corporation, was required by subpoena to produce the corporate books in his custody before a grand jury. He appeared before the grand jury but refused to deliver up the records on the ground that their contents would tend to incriminate him, and claimed privilege under the Fifth Amendment. On review in this Court of the judgment committing him for contempt, Wilson based his defense in part on the theory that he would have been protected in his constitutional privilege against self-incrimination had he been sworn as a witness, and that the government’s failure to permit him to be sworn could not deprive him of such protection.22 This argument was disposed [17]*17of by the Court simply on the ground that a corporate officer has no such constitutional privilege as to corporate records in his possession, even though they contain entries made by himself which disclose his crime. Mr. Justice Hughes, announcing the opinion of the Court, based the decision on the reasoning (which this Court recently cited with approval, in Davis v. United States, 328 U. S. 582, 589-90 [1946]) that
“the physical custody of incriminating documents does not of itself protect the custodian against their compulsory production. The question still remains with respect to the nature of the documents and the capacity in which they are held. It may yet appear that they are of a character which subjects them to the scrutiny demanded and that the custodian has voluntarily assumed a duty which overrides his claim of privilege. . . . The principle applies not only to public documents in public offices, but also to records required by law to be kept in order that there may be suitable information of transactions which are the appropriate subjects of governmental regulation and the enforcement of restrictions validly established. There the privilege, which exists as to private papers, cannot be maintained.” 23
As illustrations of documents meeting this “required records” test, the Court cited with approval state supreme court decisions that business records kept under requirement of law by private individuals in unincorporated enterprises were “ 'public documents, which the defendant was required to keep, not for his private uses, but for the benefit of the public, and for public. [18]*18inspection.' ”24 The non-corporate records treated as public in those cases concerned such individuals as druggists required by statute to keep a record of all sales of intoxicating liquors.25 The corporate and non-corpo[19]*19rate businesses required by the Price Control Act to keep records embrace a much greater number of enterprises than those similarly regulated by the states and municipalities. But, since it is conceded that the increased scope of regulation under the wartime measure here involved does not render that Act unconstitutional, the “required records” doctrine which this Court approved as applied to non-corporate businessmen in the state cases would appear equally applicable in the case at bar.
In the Heike case, this Court, per Holmes, J., laid down a standard for the construction of statutory immunity provisos which clearly requires affirmance of the decision of the circuit court here the obvious purpose of the statute is to make evidence available and compulsory that otherwise could not be got. We see no reason for supposing that the act offered a gratuity to crime. It should he construed, so far as its words fairly allow the construction, as coterminous with what otherwise would have been the privilege of the person concerned.” 26 In view of the clear rationale in Wilson, taken together with the ruling in Heike as to how statutory immunity provisos should be construed, the conclusion seems inevitable that Congress must have intended the immunity proviso in the Price Control Act to be coterminous with what would otherwise have been the constitutional privilege of petitioner in the case at bar. [20]*20Since he could assert no valid privilege as to the required records here in question, he was entitled to no immunity-under the statute thus viewed.
The traditional rule that re-enactment of a statute creates a presumption of legislative adoption of previous judicial construction may properly be applied here, since the Court in Heike regarded the 1903 immunity statute there construed as identical, in policy and in the scope of immunity furnished, with the Compulsory Testimony Act of 1893, which has been re-enacted by incorporation into the Price Control Act.
In addition, scrutiny of the precise wording of § 202 (g) of the latter statute indicates that the draftsmen of that section went to some pains to ensure that the immunity provided for would be construed by the courts as being so limited. The construction adopted in the Heike decision was rendered somewhat difficult because neither the Compulsory Testimony Act of 1893 nor the immunity proviso in the 1903 Act made any explicit reference to the constitutional privilege against self-incrimination, with whose scope the Court nonetheless held the immunity to be coterminous. Section 202 (g), on the other hand, follows a pattern set by the Securities Act of 1933 and expressly refers to that privilege, thus apparently seeking to make it doubly certain that the courts would construe the immunity there granted as no broader than the privilege:
“No person shall be excused from complying with any requirements under this section because of his privilege against self-incrimination, but the immunity provisions of the Compulsory Testimony Act of Feb. 11, 1893 . . . shall apply with respect to any individual who specifically claims such privilege.”
A comparison of the precise wording of § 202 (g) with the wording of immunity provisions contained in earlier [21]*21statutes27 readily suggests one function intended by the drafters of § 202 (g) to be performed by the additional phrases expressly referring to “privilege” — viz., that of underlining the legislative intention of requiring an exchange of constitutional privilege for immunity, an intent which the Court had previously thought discernable even in the less obvious terms used by the drafters of the earlier statutes. Thus the immunity provisions of the Compulsory Testimony Act can be relied upon here only if the two prerequisites set forth in § 202 (g) are' satisfied: (1) that the person seeking to avail himself of the immunity could actually have been excused, in the absence [22]*22of this section, from complying with any of its requirements because of his constitutional privilege against self-incrimination, and (2) that the person specifically claim such privilege. Obviously if prerequisite (1) is not fulfilled, the mere fact that the person specifically claims a non-existent privilege was not intended by Congress to entitle him to the benefit of the immunity. And this is so whether the statute be construed with particular reference to its grammar, its historical genesis, or its rational function.
Petitioner does not deny that the actual existence of a genuine privilege against self-incrimination is an absolute prerequisite for the attainment of immunity under § 202 (g) by a corporate officer who has been compelled by subpoena to produce required records; and that, under the Heike ruling, the assertion of a claim to such a privilege in connection with records which are in fact non-privileged is unavailing to secure immunity, where the claimant is a corporate officer. But, while conceding that the statute should be so construed where corporate officials are concerned, the petitioner necessarily attributes to Congress the paradoxical intention of awarding immunity in exchange for a claim of privilege as to records of a claimant engaged in non-corporate business, though his business is similarly subjected to governmental price control, and its required records are, under the Wilson rationale, similarly non-privileged.
The implausibility of any such interpretation of congressional intent is highlighted by the unquestioned fact that Congress provided for price regulations enforcible against unincorporated entrepreneurs as well as corporate industry. It is also unquestionable that Congress, to ensure that violations of the statute should not go unpunished, required records to be kept of all relevant buying and selling transactions by all individual and corporate business subject to the statute. If these aspects of con[23]*23gressional intention be conceded, it is most difficult to comprehend why Congress should be assumed to have differentiated sub silentio, for purposes of the immunity proviso, between records required to be kept by individuals and records required to be kept by corporations. Such an assumption carries with it the incongruous result that individuals forced to produce records required to be kept for the Administrator’s inspection and use in enforcing the price regulations would be given a bonus of immunity if engaged in non-corporate business, thus rendering the records of non-corporate enterprise virtually useless for enforcement purposes,28 whereas individuals disclosing the very same type of required records but engaged in corporate enterprise would not be given that bonus. In effect, this is to say that Congress intended the immunity proviso to frustrate a major aim of its statutory requirement of record-keeping and record in[24]*24spection so far as it applies to non-corporate businessmen, but not so far as it applies to corporate officers.29
It is contended that to construe the immunity proviso as we have here is to devitalize, if not render meaningless, the phrase “any requirements” 30 which appears in the opening clause of § 202 (g): “No person shall be excused from complying with any requirements under this section because of his privilege against self-incrimination . . . .” It is urged that, since § 202 includes among its require-[25]*25merits the furnishing of information under oath, the making and keeping of records and reports, the inspection and copying of records and other documents, and the appearing and testifying or producing of documents, the immunity provided must cover compliance with any one of these requirements. The short answer to that contention is that the immunity provided does cover compliance with any of these requirements as to which a person would have been excused from compliance because of his privilege, were it not for the statutory grant of immunity in exchange for such privilege,31 The express language of the proviso, as well as its historical background, readily suggests this reasonable interpretation. Even those who oppose this interpretation must and do concede that Congress had no intention of removing the excuse of privilege where the privilege is absent from the outset because the records whose production is ordered and concerning which privilege is asserted are corporate records. If this concession is made, surely logic as well as history requires a similar reading of the proviso in connection with validly required non-corporate records, as to which privilege is similarly absent from the outset.
If the contention advanced against our interpretation be valid, the Court must have erred in its construction of the immunity proviso in the Heike case. For the 1893 Act, 49 U. S. C. § 46, which it was in effect construing, provides that, “No person shall be excused [26]*26from attending and testifying or from producing books, papers, tariffs, contracts, agreements, and documents before the Interstate Commerce Commission ... for the reason that the testimony or evidence, documentary or otherwise, required of him, may tend to criminate him or subject him to a penalty or forfeiture. But no person shall be prosecuted ... for or on account of any transaction . . . concerning which he may testify, or produce evidence, documentary or otherwise . . . Thus the immunity part of the 1893 statute extended to any documentary as well as oral testimony concerning which there might be a claim of privilege. And included among the documents which the immunity-seeker might be compelled to produce were records maintained by common carriers in compliance with the requirements of the Interstate Commerce Act,32 and hence obviously within the definition of public records set forth in the Wilson and Heike decisions. If the reasoning advanced against the interpretation of § 202 (g) wje have proposed were valid, then it might equally well be contended that the Court in the Heike decision devitalized, if not rendered meaningless the phrase “documentary or otherwise” in the immunity section of the 1893 Act.
Actually, neither the interpretation as applied in the Heike decision nor as expounded here renders meaningless any of the words in the immunity provision. In each case, the immunity proviso is set forth in conjunction with record-keeping requirements. And in each case, where the immunity provided concerns documents whose production might otherwise be excused on the ground of [27]*27privilege, the documents referred to are all writings whose keeping as records has not been required by valid statute or regulation. Of course all oral testimony by individuals can properly be compelled only by exchange of immunity for waiver of privilege.33
[28]*28The Court in the Heike case was confronted with the further contention that the 1903 immunity statute, which was immediately before it, had been passed when “there was an imperious popular demand that the inside working of the trusts should be investigated, and that the people and Congress cared so much to secure the necessary evidence that they were willing that some guilty persons should escape, as that reward was necessary to the end.” 34 In the light of the express statements in the legislative history of the Price Control Act as to the enforcement role of the investigatory powers, such an argument would hardly be tenable in the present case. Yet even in the Heike case where such an argument had some elements of plausibility, the Court had no difficulty in rejecting it in favor of the Government’s contention that “the statute should be limited as nearly as may be by the boundaries of the constitutional privilege of which it takes the place.” 35
As a final answer, an understanding of the 1893 immunity provision, based on its full historical context, should suffice to explain the limited function contemplated by Congress in incorporating that provision into the 1942 statute. The 1893 provision was enacted merely to provide an immunity sufficiently broad to be an ade[29]*29quate substitute for the constitutional privilege, since previous statutory provision for immunity had been found by the Court in Counselman v. Hitchcock, 142 U. S. 547 (1892), not to be coextensive with the privilege, thus rendering unconstitutional the statutory requirements for compulsory production of privileged documents and oral testimony.36
The suggestion has been advanced that the scope of the immunity intended by Congress should be ascertained, not by reference to the judicial and legislative history considered above, but by reference to the principle expounded in Federal Trade Comm’n v. American Tobacco Co., 264 U. S. 298, 307 (1924), of construing a broad grant of statutory authority so as to avoid attributing to Congress “an intent to defy the Fourth Amendment or even to come so near to doing so as to raise a serious question of constitutional law.”
It is interesting to note that Congress, in enacting the Price Control Bill, apparently did intend to rely upon the principle of American Tobacco in circumstances similar to those in which that principle was originally applied: namely, to insure that the power of inspection or examination would not conflict with the prohibition against unreasonable searches and seizures contained in the Fourth Amendment. Senator Brown, who was chairman of the sub-committee on the Price Control Bill and one of the managers on the part of the Senate [30]*30appointed to confer with the House managers on the Senate amendments, expressly stated it to be the view of the conferees that § 202 (a), which contained broad authorization to the Administrator to “obtain such information as he deems necessary or proper to assist him” in his statutory duties, was intended solely to empower the Administrator to “obtain relevant data to enable him properly to discharge his functions, preferably by requiring the furnishing of information under oath or affirmation or otherwise as he may determine. It is not intended, nor is any other provision of the act intended, to confer any power of inspection or examination which might conflict with the fourth amendment of the Constitution of the United States. See opinion of Justice Holmes in Federal Trade Commission v. American Tobacco Co., 264 U. S. 298, 307.” 37
It was the abuse of the subpoena power to obtain irrelevant data in the course of a “fishing expedition” with which the Court was concerned in that case. It is clear that if the Administrator sought to obtain data irrelevant to the effective administration of the statute and if his right of access was challenged on the ground that the evidence sought was “plainly incompetent or irrelevant to any lawful purpose”38 of the Administrator, that objection could sustain a refusal by the district court to issue a subpoena or other writ to compel inspection. But there is no indication in the legislative history that Congress intended the American Tobacco principle of construction to govern the immunity proviso of subsection (g), particularly since the scope of that proviso had been so well demarcated by the courts prior to its 1942 re-enactment. And it is not insignificant that the one rule of construction which this Court has, in the past, directly and [31]*31expressly applied to the immunity proviso — that “It should be construed, so far as its words fairly allow the construction, as coterminous with what otherwise would have been the privilege of the person concerned”39 — was enunciated by Mr. Justice Holmes, who gave no sign of repudiating that principle by his subsequent statements in the American Tobacco case.
Even if the evidence of congressional intent contained in the legislative history were less clear-cut and persuasive, and constitutional doubts more serious than they appear to us, we would still be unconvinced as to the applicability of the American Tobacco standard to the construction of the immunity proviso in relation to documentary evidence which is clearly and undeniably relevant, and the recording and keeping of which the Administrator has properly required in advance. For, in construing statutory immunities in such circumstances, we must heed the equally well-settled doctrine of this Court to read a statute, assuming that it is susceptible of either of two opposed interpretations, in the manner which effectuates rather than frustrates the major purpose of the legislative draftsmen. The canon of avoidance of constitutional doubts must, like the “plain meaning” rule, give way where its application would produce a futile result, or an unreasonable result “plainly at variance with the policy of the legislation as a whole.”40 In the present case, not merely does the construction [32]*32put forward by the petitioner frustrate the congressional intent as manifested by the legislative history, but it also shuts out the illumination that emanates from key words and phrases in the section when considered, as above, in the context of the history of the Compulsory Testimony Act of 1893, and the construction that had been placed upon it and similar provisos, prior to its incorporation into the Price Control Act.
There remains for consideration only the question as to whether serious doubts of constitutionality are raised if the Price Control Act is thus construed. This issue was not duly raised by petitioner, and it becomes relevant, if at all, only because such doubts are now said to be present if the immunity proviso is interpreted as set forth above.
It may be assumed at the outset that there are limits which the Government cannot constitutionally exceed in requiring the keeping of records which may be inspected by an administrative agency and may be used in prosecuting statutory violations committed by the record-keeper himself. But no serious misgiving that those bounds have been overstepped would appear to be evoked when there is a sufficient relation between the activity sought to be regulated and the public concern so that the Government can constitutionally regulate or forbid the basic activity concerned, and can constitutionally require the keeping of particular records, subject to inspection by the Administrator. It is not questioned here that Congress has constitutional authority to prescribe commodity prices as a war emergency measure, and that the licensing and record-keeping requirements of the Price Control Act represent a legitimate exercise of that power.41 Accordingly, the principle enunciated in the Wilson case, and reaffirmed as recently as the Davis case, is clearly applicable here: [33]*33namely, that the privilege which exists as to private papers cannot be maintained in relation to “records required by law to be kept in order that there may be suitable information of transactions which are the appropriate subjects of governmental regulation and the enforcement of restrictions validly established.”42
[34]*34Even the dissenting Justices in the Davis case conceded that “there is an important difference in the constitutional protection afforded their possessors between papers exclusively private and documents having public aspects,”43 a difference whose essence is that the latter papers, “once they have been legally obtained, are available as evidence.” 44 In the case at bar, it cannot be doubted that the sales record which petitioner was required to keep as a licensee under the Price Control Act has “public aspects.” Nor can there be any doubt that when it was obtained by the Administrator through the use of a subpoena, as authorized specifically by § 202 (b) of the statute, it was “le-[35]*35gaily obtained” and hence “available as evidence.” 45 The record involved in the case at bar was a sales record required to be maintained under an appropriate regulation, its relevance to the lawful purpose of the Administrator is unquestioned, and the transaction which it recorded was one in which the petitioner could lawfully engage solely by virtue of the license granted to him under the statute.46
In the view that we have taken of the case, we find it unnecessary to consider the additional contention by the Government that, in any event, no immunity attaches to the production of the books by the petitioner because the [36]*36connection between the books and the evidence produced at the trial was too tenuous to justify the claim.
For the foregoing reasons, the judgment of the Circuit Court of Appeals is
Affirmed.