delivered the opinion of the Court.
Title I of Pub. L. 93-526, 88 Stat. 1695, note following 44 U. S. C. § 2107 (1970 ed., Supp. V), the Presidential Recordings and Materials Preservation Act (hereafter Act), directs the Administrator of General Services, an official of the Executive Branch, to take custody of the Presidential papers and tape recordings of appellant, former President Richard M. Nixon, and promulgate regulations that (1) provide for the orderly processing and screening by Executive Branch archivists of such materials for the purpose of returning to appellant those that are personal and private in nature, and (2) determine the terms and conditions upon which public access may eventually be had to those materials that are retained. The question for decision is whether Title I is unconstitutional on its face as a violation of (1) the separation of powers; (2) Presidential privilege doctrines; (3) appellant’s privacy interests; (4) appellant’s First Amendment associational rights; or (5) the Bill of Attainder Clause.
On December 19, 1974, four months after appellant resigned as President of the United States, his successor, President Gerald R. Ford, signed Pub. L. 93-526 into law. The next *430day, December 20, 1974, appellant filed this action in the District Court for the District of Columbia, which under § 105 (a) of the Act has exclusive jurisdiction to entertain complaints challenging the Act’s legal or constitutional validity, or that of any regulation promulgated by the Administrator. Appellant’s complaint challenged the Act’s constitutionality on a number of grounds and sought declaratory and injunctive relief against its enforcement. A three-judge District Court was convened pursuant to 28 U. S. C. §§ 2282, 2284.1 Because regulations required by § 104 of the Act governing public access to the materials were not yet effective, the District Court held that questions going to the possibility of future public release under regulations yet to be published were not ripe for review. It found that there was “no need and no justification for this court now to reach constitutional claims directed at the regulations . . . the promulgation of [which] might eliminate, limit, or cast [the constitutional claims] in a different light.” 408 F. Supp. 321, 336 (1976). Accordingly, the District Court limited review “to consideration of the propriety of injunctive relief against the alleged facial unconstitutionality of the statute,” id., at 335, and held that the challenges to the facial constitutionality of the Act were without merit. It therefore dismissed the complaint. Id., at 374-375. We noted probable jurisdiction, 429 U. S. 976 (1976). We affirm.
I
The Background
The materials at issue consist of some 42 million pages of documents and some 880 tape recordings of conversations. Upon his resignation, appellant directed Government archivists to pack and ship the materials to him in California. This *431shipment was delayed when the Watergate Special Prosecutor advised President Ford of his continuing need for the materials. At the same time, President Ford requested that the Attorney General give his opinion respecting ownership of the materials. The Attorney General advised that the historical practice of former Presidents and the absence of any governing statute to the contrary supported ownership in the appellant, with a possible limited exception.2 43 Op. Atty. Gen. No, 1 (1974), App. 220-230. The Attorney General’s opinion emphasized, however:
“Historically, there has been consistent acknowledgement that Presidential materials are peculiarly affected by a public interest which may justify subjecting the absolute ownership rights of the ex-President to certain limitations directly related to the character of the documents as records of government activity.” Id., at 226.
On September 8, 1974, after issuance of the Attorney General’s opinion, the Administrator of General Services, Arthur F. Sampson, announced that he had signed a depository agreement with appellant under the authority of 44 U. S. C. § 2107. 10 Weekly Comp, of Pres. Doc. 1104 (1974). We shall also refer to the agreement as the Nixon-Sampson agreement. See Nixon v. Sampson, 389 F. Supp. 107, 160-162 (DC 1975) (App. A). The agreement recited that appellant retained “all legal and equitable title to the Materials, including all literary property rights,” and that the materials accordingly were to be “deposited temporarily” near appellant’s California home in an “existing facility belonging to the United States.” Id., at 160. The agreement stated further that appellant’s purpose was “to donate” the materials to the United States “with appropriate *432restrictions.” Ibid. It was provided that all of the materials “shall be placed within secure storage areas to which access can be gained only by use of two keys,” one in appellant’s possession and the other in the possession of the Archivist of the United States or members of his staff. With exceptions not material here, appellant agreed “not to withdraw from deposit any originals of the materials” for a period of three years, but reserved the right to “make reproductions” and to authorize other persons to have access on conditions prescribed by him. After three years, appellant might exercise the “right to withdraw from deposit without formality any or all of the Materials . . . and to retain . . . [them] for any purpose . . .” determined by him. Id., at 161.
The Nixon-Sampson agreement treated the tape recordings separately. They were donated to the United States “effective September 1, 1979,” and meanwhile “shall remain on deposit.” It was provided however that “[subsequent to September 1, 1979 the Administrator shall destroy such tapes as [Mr. Nixon] may direct” and in any event the tapes “shall be destroyed at the time of [his] death or on September 1, 1984, whichever event shall first occur.” Ibid. Otherwise the tapes were not to be withdrawn, and reproductions would be made only by “mutual agreement.” Id., at 162. Access until September 1, 1979, was expressly reserved to appellant, except as he might authorize access by others on terms prescribed by him.
Public announcement of the agreement was followed 10 days later, September 18, by the introduction of S. 4016 by 13 Senators in the United States Senate. The bill, which became Pub. L. 93-526 and was designed, inter alia, to abrogate the Nixon-Sampson agreement, passed the Senate on October 4, 1974. It was awaiting action in the House of Representatives when on October 17, 1974, appellant filed suit in the District Court seeking specific enforcement of the Nixon-Sampson agreement. That action was consolidated with other suits seeking access to Presidential materials pur*433suant to the Freedom of Information Act, 5 U. S. C. § 552 (1970 ed. and Supp. V), and also seeking injunctive relief against enforcement of the agreement. Nixon v. Sampson, supra.3 The House passed its version of the Senate bill on December 3, 1974. The final version of S. 4016 was passed on December 9, 1974, and President Ford signed it into law on December 19.
II
The Act
Public Law 93-526 has two Titles. Title I, the challenged Presidential Recordings and Materials-Preservation Act, consists of §§ 101 through 106. Title II, the Public Documents Act, amends Chapter 33 of Title 44, United States Code, to add §§ 3315 through 3324 thereto, and establish the National Study Commission on Records and Documents of Federal Officials.
Section 101 (a) of Title I directs that the Administrator of General Services, notwithstanding any other law or agreement or understanding (e. g., the Nixon-Sampson agreement), “shall receive, obtain, or retain, complete possession and control of all original tape recordings of conversations which were recorded or caused to be recorded by any officer or employee of the Federal Government and which—
“(1) involve former President Richard M. Nixon or other individuals who, at the time of the conversation, were employed by the Federal Government;
*434“(2) were recorded in the White House or in the office of the President in the Executive Office Buildings located in Washington, District of Columbia; Camp David, Maryland; Key Biscayne, Florida; or San Clemente, California; and
“(3) were recorded during the period beginning January 20,1969, and ending August 9,1974.”
Section 101 (b) provides that notwithstanding any such agreement or understanding, the Administrator also “shall receive, retain, or make reasonable efforts to obtain, complete possession and control of all papers, documents, memorandums, transcripts, and other objects and materials which constitute the Presidential historical materials [as defined by 44 U. S. C. § 2101] of Richard M. Nixon, covering the period beginning January 20, 1969, and ending August 9, 1974.”
Section 102 (a) prohibits destruction of the tapes or materials except as may be provided by law, and § 102 (b) makes them available (giving priority of access to the Office of the Watergate Special Prosecutor) in response to court subpoena or other legal process, or for use in judicial proceedings. This was made subject, however, “to any rights, defenses, or privileges which the Federal Government or any person may invoke . . . .” Section 102 (c) affords appellant, or any person designated by him in writing, access to the recordings and materials for any purpose consistent with the Act “subsequent and subject to the regulations” issued by the Administrator under § 103. See n. 46, infra. Section 102 (d) provides for access according to § 103 regulations by any agency or department in the Executive Branch for lawful Government use. Section 103 requires custody of the tape recordings and materials to be maintained in Washington except as may otherwise be necessary to carry out the Act, and directs that the Administrator promulgate regulations necessary to assure their protection from loss or destruction and to prevent access to them by unauthorized persons.
*435Section 104, in pertinent part, directs the Administrator to promulgate regulations governing public access to the tape recordings and materials. Section 104 (a) requires submission of proposed regulations to each House of Congress, the regulations to take effect under § 104 (b)(1) at the end of 90 legislative days unless either the House or the Senate adopts a resolution disapproving them. The regulations must take into account seven factors specified in § 104 (a), namely:
“(1) the need to provide the public with the full truth, at the earliest reasonable date, of the abuses of governmental power popularly identified under the generic term 'Watergate’;
“(2) the need to make such recordings and materials available for use' in judicial proceedings;
“(3) the need to prevent general access, except in accordance with appropriate procedures established for use in judicial proceedings to information relating to the Nation’s security;
“(4) the need to protect every individual’s right to a fair and impartial trial;
"(5) the need to protect any party’s opportunity to assert any legally or constitutionally based right or privilege which would prevent or otherwise limit access to such recordings and materials;
“(6) the need to provide public access to those materials which have general historical significance, and which are not likely to be related to the need described in paragraph (1); and
"(7) the need to give to Richard M. Nixon, or his heirs, for his sole custody and use, tape recordings and other materials which are not likely to be related to the need described in paragraph (1) and are not otherwise of general historical significance.”
Section 105 (a) vests the District Court for the District of Columbia with exclusive jurisdiction not only to hear *436constitutional challenges to the Act, but also to hear challenges to the validity of any regulation, and to decide actions involving questions of title, ownership, custody, possession, or control of any tape or materials, or involving payment of any award of just compensation required by § 105 (c) when a decision of that court holds that any individual has been deprived by the Act of private property without just compensation. Section 105 (b) is a severability provision providing that any decision' invalidating a provision of the Act or a regulation shall not affect the validity or enforcement of any other provision or regulation. Section 106 authorizes appropriation of such sums as may be necessary to carry out the provisions of the Title.
Ill
The Scope of the Inquiry
The District Court correctly focused on the Act’s requirement that the Administrator of General Services administer the tape recordings and materials placed in his custody only under regulations promulgated by him providing for the orderly processing of such materials for the purpose of returning to appellant such of them as are personal and private in nature, and of determining the terms and conditions upon which public access may eventually be had to those remaining in the Government’s possession. The District Court also noted that in designing the regulations, the Administrator must consider the need to protect the constitutional rights of appellant and other individuals against infringement by the processing itself or, ultimately, by public access to the materials retained. 408 F. Supp., at 334-340. This construction is plainly required by the wording of §§ 103 and 104.4
*437Regulations implementing §§102 and 103, which did not require submission to Congress, and which regulate access and screening by Government archivists, have been promulgated, 41 CFR § 105-63 (1976). Public-access regulations that must be submitted to Congress under § 104 (a) have not, however, become effective. The initial set proposed by the Administrator was disapproved pursuant to § 104 (b) (1) by Senate Resolution. S. Res. 244, 94th Cong., 1st Sess. (1975); 121 Cong. Rec. 28609-28614 (1975)., The Senate also disapproved seven provisions of a proposed second set, although that set had been withdrawn. S. Res. 428, 94th Cong., 2d Sess. (1976); 122 Cong. Rec. 10159-10160 (1976). The House disapproved six provisions of a third set. H. R. Res. 1505, 94th Cong., 2d Sess. (1976). The Administrator is of the view that regulations cannot become effective except as a package and consequently is preparing a fourth set for submission to Congress. Brief for Federal Appellees 8-9, n. 4.
*438The District Court therefore concluded that as no regulations under § 104 had yet taken effect, and as such regulations once effective were explicitly made subject to judicial review under § 105, the court could consider only the injury to appellant’s constitutionally protected interests allegedly worked by the taking of his Presidential materials into custody for screening by Government archivists. 408 F. Supp., at 339-340. Judge McGowan, writing for the District Court, quoted the following from Watson v. Buck, 313 U. S. 387, 402 (1941):
“No one can foresee the varying applications of these separate provisions which conceivably might be made. A law which is constitutional as applied in one manner may still contravene the Constitution as applied in another. Since all contingencies of attempted enforcement cannot be envisioned in advance of those applications, courts have in the main found it wiser to delay passing upon the constitutionality of all the separate phases of a comprehensive statute until faced with cases involving particular provisions as specifically applied to persons who claim to be injured. Passing upon the possible significance of the manifold provisions of a broad statute in advance of efforts to apply the separate provisions is analogous to rendering an advisory opinion upon a statute or a declaratory judgment upon a hypothetical case.” 408 F. Supp., at 336.
Only this Term we applied this principle in an analogous situation in declining to adjudicate the constitutionality of regulations of the Administrator of the Environmental Protection Agency that were in process of revision, stating: “For [the Court] to review regulations not yet promulgated, the final form of which has been only hinted at, would be wholly novel.” EPA v. Brown, 431 U. S. 99, 104 (1977). See also Thorpe v. Housing Authority, 393 U. S. 268, 283-284 (1969); Rosenberg v. Fleuti, 374 U. S. 449, 451 (1963); United States v. Raines, 362 U. S. 17, 20-22 (1960); Harmon v. Brucker, 355 *439U. S. 579 (1958). We too, therefore, limit our consideration of the merits of appellant’s several constitutional claims to those addressing the facial validity of the provisions of the Act requiring the Administrator to take the recordings and materials into the Government’s custody subject to screening by Government archivists.
The constitutional questions to be decided are, of course, of considerable importance. They touch the relationship between two of the three coordinate branches of the Federal Government, the Executive and the Legislative, and the relationship of appellant to his Government. They arise in a context unique in the history of the Presidency and present issues that this Court has had no occasion heretofore to address. Judge McGowan, speaking for the District Court, comprehensively canvassed all the claims, and in a thorough opinion, concluded that none had merit. Our independent examination of the issues brings us to the same conclusion, although our analysis differs somewhat on some questions.
IV
Claims Concerning the Autonomy of the Executive Branch
The Act was the product of joint action by the Congress and President Ford, who signed the bill into law. It is therefore urged by intervenor-appellees that, in this circumstance, the case does not truly present a controversy concerning the separation of powers, or a controversy concerning the Presidential privilege of confidentiality, because, it is argued, such claims may be asserted only by incumbents who are presently responsible to the American people for their action. We reject the argument that only an incumbent President may assert such claims and hold that appellant, as a former President, may also be heard to assert them. We further hold, however, that neither his separation-of-powers claim nor his claim of breach of constitutional privilege has merit.
Appellant argues broadly that the Act encroaches upon the *440Presidential prerogative to control internal operations of the Presidential office and therefore offends the autonomy of the Executive Branch. The argument is divided into separate but interrelated parts.
First, appellant contends that Congress is without power to delegate to a subordinate officer of the Executive Branch the decision whether to disclose Presidential materials and to prescribe the terms that govern any disclosure. To do so, appellant contends, constitutes, without more, an impermissible interference by the Legislative Branch into matters inherently the business solely of the Executive Branch.
Second, appellant contends, somewhat more narrowly, that by authorizing the Administrator to take custody of all Presidential materials in a “broad, undifferentiated’' manner, and authorizing future publication except where a privilege is affirmatively established, the Act offends the presumptive confidentiality of Presidential communications recognized in United States v. Nixon, 418 U. S. 683 (1974). He argues that the District Court erred in two respects in rejecting this contention. Initially, he contends that the District Court erred in distinguishing incumbent from former Presidents in evaluating appellant’s claim of confidentiality. Appellant asserts that, unlike the very specific privilege protecting against disclosure of state secrets and sensitive information concerning military or diplomatic matters, which appellant concedes may be asserted only by an incumbent President, a more generalized Presidential privilege survives the termination of the President-adviser relationship much as the attorney-client privilege survives the relationship that creates it. Appellant further argues that the District Court erred in applying a balancing test to his claim of Presidential privilege and in concluding that, notwithstanding the fact that some of the materials might legitimately be included within a claim of Presidential confidentiality, substantial public interests outweighed and justified the limited *441inroads on Presidential confidentiality necessitated by the Act’s provision for Government custody and screening of the materials. Finally, appellant contends that the Act’s authorization of the process of screening the materials itself violates the privilege and will chill the future exercise of constitutionally protected executive functions, thereby impairing the ability of future Presidents to obtain the candid advice necessary to the conduct of their constitutionally imposed duties.
A
Separation of Powers
We reject at the outset appellant’s argument that the Act’s regulation of the disposition of Presidential materials within the Executive Branch constitutes, without more, a violation of the principle of separation of powers. Neither President Ford nor President Carter supports this claim. The Executive Branch became a party to the Act’s regulation when President Ford signed the Act into law, and the administration of President Carter, acting through the Solicitor General, vigorously supports affirmance of the District Court’s judgment sustaining its constitutionality. Moreover, the control over the materials remains in the Executive Branch. The Administrator of General Services, who must promulgate and administer the regulations that are the keystone of the statutory scheme, is himself an official of the Executive Branch, appointed by the President. The career archivists appointed to do the initial screening for the purpose of selecting out and returning to appellant his private and personal papers similarly are Executive Branch employees.
Appellant’s argument is in any event based on an interpretation of the separation-of-powers doctrine inconsistent with the origins of that doctrine, recent decisions of the Court, and the contemporary realities of our political system. True, it has been said that “each of the three general departments of government [must remain] entirely free from the control or *442coercive influence, direct or indirect, of either of the others . . . Humphrey’s Executor v. United States, 295 U. S. 602, 629 (1935), and that “[t]he sound application of a principle that makes one master in his own house precludes him from imposing his control in the house of another who is master there.” Id., at 630. See also O’Donoghue v. United States, 289 U. S. 516 (1933); Springer v. Philippine Islands, 277 U. S. 189, 201 (1928).
But the more pragmatic, flexible approach of Madison in the Federalist Papers and later of Mr. Justice Story5 was expressly affirmed by this Court only three years ago in United States v. Nixon, supra. There the same broad argument concerning the separation of powers was made by appellant in the context of opposition to a subpoena duces tecum of the Watergate Special Prosecutor for certain Presidential tapes and documents of value to a pending criminal investigation. Although acknowledging that each branch of the Government has the duty initially to interpret the Constitution for itself, and that its interpretation of its powers is due *443great respect from the other branches, 418 U. S., at 703,'the Court squarely rejected the argument that the Constitution contemplates a complete division of authority between the three branches. Rather, the unanimous Court essentially embraced Mr. Justice Jackson’s view, expressed in his concurrence in Youngstown Sheet & Tube Co. v. Sawyer, 343 U. S. 579, 635 (1952).
“In designing the structure of our Government and dividing and allocating the sovereign power among three co-equal branches, the Framers of the Constitution sought to provide a comprehensive system, but the separate powers were not intended to operate with absolute independence.” 418 U. S., at 707 (emphasis supplied).
Like the District Court, we therefore find that appellant’s argument rests upon an “archaic view of the separation of powers as requiring three airtight departments of government,” 408 F. Supp., at 342.6 Rather, in determining whether the Act disrupts the proper balance between the coordinate branches, the proper inquiry focuses on the extent to which it prevents the Executive Branch from accomplishing its constitutionally assigned functions. United States v. Nixon, 418 U. S., at 711-712. Only where the potential for disruption is present must we then determine whether that impact is justified by an overriding need to promote objectives within the constitutional authority of Congress. Ibid.
It is therefore highly relevant that the Act provides for custody of the materials in officials of the Executive Branch and that employees of that branch have access to the materials only “for lawful Government use, subject to the [Adminis*444trator’s] regulations.” § 102 (d); 41 CFR §§ 105-63.205, 105-63.206, and 105-63.302 (1976). For it is clearly less intrusive to place custody and screening of the materials within the Executive Branch itself than to have Congress or some outside agency perform the screening function. While the materials may also be made available for use in judicial proceedings, this provision is expressly qualified by any rights, defense, or privileges that any person may invoke including, of course, a valid claim of executive privilege. United States v. Nixon, supra. Similarly, although some of the materials may eventually be made available for public access, the Act expressly recognizes the need both “to protect any party’s opportunity to assert any legally or constitutionally based right or privilege,” § 104 (a) (5), and to return purely private materials to appellant, § 104 (a)(7). These provisions plainly guard against-disclosures barred by any defenses or privileges available to appellant or the Executive Branch.7 And appellant himself concedes that the Act “does not make the presidential materials available to the Congress — except insofar as Congressmen are members of the public and entitled to access when the public has it.” Brief for Appellant 119. The Executive Branch remains in full control of the Presidential materials, and the Act facially is designed to ensure that the materials can be released only when release is not barred by some applicable privilege inherent in that branch.
Thus, whatever are the future possibilities for constitutional *445conflict in the promulgation of regulations respecting public access to particular documents, nothing contained in the Act renders it unduly disruptive of the Executive Branch and, therefore, unconstitutional on its face. And, of course, there is abundant statutory precedent for the regulation and mandatory disclosure of documents in the possession of the Executive Branch. See, e. g., the Freedom of Information Act, 5 U. S. C. § 552 (1970 ed. and Supp. V); the Privacy Act of 1974, 5 U. S. C. § 552 (a) (1970 ed., Supp. V); the Government in the Sunshine Act, 5 U. S. C. § 552b (1976 ed.); the Federal Records Act, 44 U. S. C. §2101 et seq.; and a variety of other statutes, e. g., 13 U. S. C. §§ 8-9 (census data); 26 U. S. C. § 6103 (tax returns). Such regulation of material generated in the Executive Branch has never been considered invalid as an invasion of its autonomy. Cf. EPA v. Mink, 410 U. S. 73, 83 (1973); FAA Administrator v. Robertson, 422 U. S. 255 (1975).8 Similar congressional power *446to regulate Executive Branch documents exists in this instance, a power that is augmented by the important interests that the Act seeks to attain. See infra, at 452-454.
B
Presidential Privilege
Having concluded that the separation-of-powers principle is not necessarily violated by the Administrator’s taking custody of and screening appellant’s papers, we next consider appellant’s more narrowly defined claim that the Presidential privilege shields these records from archival scrutiny. We start with what was established in United States v. Nixon, supra — that the privilege is a qualified one.9 Appellant had argued in that case that in camera inspection by the District Court of Presidential documents and materials subpoenaed by the Special Prosecutor would itself violate the privilege without regard to whether the documents were protected from public disclosure. The Court disagreed, stating that “neither the doctrine of separation of powers, nor the need for confidentiality of high-level communications, without more, can sustain an absolute, unqualified Presidential privilege . . . .”10 *447418 U. S., at 706. The Court recognized that the privilege of confidentiality of Presidential communications derives from the supremacy of the Executive Branch within its assigned area of constitutional responsibilities,11 but distinguished a President’s “broad, undifferentiated claim of public interest in the confidentiality of such [communications]” from the more particularized and less qualified privilege relating to the need “to protect military, diplomatic, or sensitive national security secrets . . . Ibid. The Court held that in the case of the general privilege of confidentiality of Presidential communications, its importance must be balanced against the inroads of the privilege upon the effective functioning of the Judicial Branch. This balance was struck against the claim of privilege in that case because the Court determined that the intrusion into the confidentiality of Presidential communications resulting from in camera inspection by the District Court, “with all the protection that a district court will be obliged to provide,” would be minimal and therefore that the claim was outweighed by “[t]he impediment that an absolute, unqualified privilege would place in the way of the primary constitutional duty of the Judicial Branch . . . .” Id., at 706-707.
Unlike United States v. Nixon, in which appellant asserted a claim of absolute Presidential privilege against inquiry by the coordinate Judicial Branch, this case initially involves appellant’s assertion of a privilege against the very *448Executive Branch in whose name the privilege is invoked. The nonfederal appellees rely on this apparent anomaly to contend that only an incumbent President can assert the privilege of the Presidency. Acceptance of that proposition would, of course, end this inquiry. The contention draws on United States v. Reynolds, 345 U. S. 1, 7-8 (1953), where it was said that the privilege “belongs to the Government and must be asserted by it: it can neither be claimed nor waived by a private party.” The District Court believed that this statement was strong support for the contention, but found resolution of the issue unnecessary. 408 F. Supp., at 343-345. It sufficed, said the District Court, that the privilege, if available to a former President, was at least one that “carries much less weight than a claim asserted by the incumbent himself.” Id., at 345.
It is true that only the incumbent is charged with performance of the executive duty under the Constitution. And an incumbent may be inhibited in disclosing confidences of a predecessor when he believes that the effect may be to discourage candid presentation of views by his contemporary advisers. 'Moreover, to the extent that the privilege serves as a shield for executive officials against burdensome requests for information which might interfere with the proper performance of their duties, see United States v. Nixon, 418 U. S., at 714; cf. Eastland v. United States Servicemen’s Fund, 421 U. S. 491, 501-503 (1975); Dombrowski v. Eastland, 387 U. S. 82, 8A-85 (1967) (per curiam), a former President is in less need of it than an incumbent. In addition, there are obvious political checks against an incumbent's abuse of the privilege.
Nevertheless, we think that the Solicitor General states the sounder view, and we adopt it:
“This Court held in United States v. Nixon . . . that the privilege is necessary to provide the confidentiality required for the President’s conduct of office. Unless he *449can give his advisers some assurance of confidentiality, a President could not expect to receive the full and frank submissions of facts and opinions upon which effective discharge of his duties depends. The confidentiality necessary to this' exchange cannot be measured by the few months or years between the submission of the information and the end of the President’s tenure; the privilege is not for the benefit of the President as an individual, but for the benefit of the Republic. Therefore the privilege survives the individual President’s tenure.” Brief for Federal Appellees 33.
At the same time, however, the fact that neither President Ford nor President Carter supports appellant’s claim detracts from the weight of his contention that the Act impermissibly intrudes into the executive function and the needs of the Executive Branch. This necessarily follows, for it must be presumed that the incumbent President is vitally concerned with and in the best position to assess the present and future needs of the Executive Branch, and to support invocation of the privilege accordingly.
The appellant may legitimately assert the Presidential privilege, of course, only as to those materials whose contents fall within the scope of the privilege recognized in United States v. Nixon, supra. In that case the Court held that the privilege is limited to communications “in performance of [a President’s] responsibilities,” 418 U. S., at 711, “of his office,” id., at 713, and made “in the process of shaping policies and making decisions,” id., at 708. Of the estimated 42 million pages of documents and 880 tape recordings whose custody is at stake, the District Court concluded that the appellant’s claim of Presidential privilege could apply at most to the 200,000 items with which the appellant was personally familiar.
The appellant bases his claim of Presidential privilege in this case on the assertion that the potential disclosure of *450communications given to the appellant in confidence would adversely affect the ability of future Presidents to obtain the candid advice necessary for effective decisionmaking. We are called upon to adjudicate that claim, however, only with respect to the process by which the materials will be screened and catalogued by professional archivists. For any eventual public access will be governed by the guidelines of § 104, which direct the Administrator to take into account “the need to protect any party’s opportunity to assert any . . . constitutionally based right or privilege,” § 104 (a) (5), and the need to return purely private materials to the appellant, §104 (a)(7).
In view of these specific directions, there is no reason to believe that the restriction on public access ultimately established by regulation will not be adequate to preserve executive confidentiality. An absolute barrier to all outside disclosure is not practically or constitutionally necessary. As the careful research by the District Court clearly demonstrates, there has never been an expectation that the confidences of the Executive Office are absolute and unyielding. All former Presidents from President Hoover to President Johnson have deposited their papers in Presidential libraries (an example appellant has said he intended to follow) for governmental preservation and eventual disclosure.12 The *451screening processes for sorting materials for lodgment in these libraries also involved comprehensive review by archivists, often involving materials upon which access restrictions ultimately have been imposed. 408 F. Supp., at 347. The expectation of the confidentiality of executive communications thus has always been limited and subject to erosion over time after an administration leaves office.
We are thus left with the bare claim that the mere screening of the materials by the archivists will impermissibly interfere with candid communication of views by Presidential advisers.13 We agree with the District Court that, thus framed, the question is readily resolved. The screening constitutes a very limited intrusion by personnél in the Executive Branch sensitive to executive concerns. These very personnel have performed the identical task in each of the Presidential *452libraries without any suggestion that such activity has in any way interfered with executive confidentiality. Indeed, in light of this consistent historical practice, past and present executive officials must be well aware of the possibility that, at some time in the future, their communications may be reviewed on a confidential basis by professional archivists. Appellant has suggested no reason why review under the instant Act, rather than the Presidential Libraries Act, is significantly more likely to impair confidentiality, nor has he called into question the District Court’s finding that the archivists’ “record for discretion in handling confidential material is unblemished.” 408 F. Supp., at 347.
Moreover, adequate justifications are shown for this limited intrusion into executive confidentiality comparable to those held to justify the in camera inspection of the District Court sustained in United States v. Nixon, supra. Congress’ purposes in enacting the Act are exhaustively treated in the opinion of the District Court. The legislative history of the Act clearly reveals that, among other purposes, Congress acted to establish regular procedures to deal with the perceived need to preserve the materials for legitimate historical and governmental purposes.14 An incumbent President should not be dependent on happenstance or the whim of a prior President when he seeks access to records of past decisions that define or channel current governmental obligations.15 Nor should the American people’s ability to recon*453struct and come to terms with their history be truncated by an analysis of Presidential privilege that focuses only on the needs of the present.16 Congress can legitimately act to rectify the hit-or-miss approach that has characterized past attempts to protect these substantial interests by entrusting the materials to expert handling by trusted and disinterested professionals.
Other substantial public interests that led Congress to seek to preserve appellant's materials were the desire to restore public confidence in our political processes by preserving the materials as a source for facilitating a full airing of the events leading to appellant’s resignation, and- Congress’ need to understand how those political processes had in fact operated in order to gauge the necessity for remedial legislation. Thus by preserving these materials, the Act may be thought to aid the legislative process and thus to be within the scope of Congress’ broad investigative power, see, e. g., Eastland v. United States Servicemen’s Fund, 421 U. S. 491 (1975). And, of course, the Congress repeatedly referred to the importance of the materials to the Judiciary in the event that they shed light upon issues in civil or criminal litigation, a social *454interest that cannot .be doubted. See United States v. Nixon, supra.17
In light of these objectives, the scheme adopted by Congress for preservation of the appellant’s Presidential materials cannot be said to be overbroad. It is true that among the voluminous materials to be screened by archivists are some materials that bear no relationship to any of these objectives (and whose prompt return to appellant is therefore mandated by § 104 (a) (7)). But these materials are commingled with other materials whose preservation the Act requires, for the appellant, like his predecessors, made no systematic attempt to segregate official, personal, and private materials. 408 P. Supp., at 355. Even individual documents and tapes often intermingle communications relating to governmental duties, and of great interest to historians or future policymakers, with private and confidential communications. Ibid.
Thus, as in the Presidential libraries, the intermingled state of the materials requires the comprehensive review and clássification contemplated by the Act if Congress’ important objectives are to be furthered. In the course of that process, the archivists will be required to view the small fraction of the materials that implicate Presidential confidentiality, as well as personal and private materials to be returned to appellant. But given the safeguards built into the Act to prevent disclosure of such materials and the minimal nature of the intrusion into the confidentiality of the Presidency, we believe that the claims of Presidential privilege clearly must yield to the important congressional purposes of preserving the materials and maintaining access to them for lawful governmental and historical purposes.
*455In short, we conclude that the screening process contemplated by the Act will not constitute a more severe intrusion into Presidential confidentiality than the in camera inspection by the District Court approved in United States v. Nixon, 418 U. S., at 706. We must, of course, presume that the Administrator and the career archivists concerned will carry out the duties assigned to them by the Act. Thus, there is no basis for appellant’s claim that the Act “reverses” the presumption in favor of confidentiality of Presidential papers recognized in United States v. Nixon. Appellant’s right to assert the privilege is specifically preserved by the Act. The guideline provisions on their face are as broad as the privilege itself. If the broadly written protections of the Act should nevertheless prove inadequate to safeguard appellant’s rights or to prevent usurpation of executive powers, there will be time enough to consider that problem in a specific factual context. For the present, we hold, in agreement with the District Court, that the Act on its face does not violate the Presidential privilege.
V
Privacy
Appellant concedes that when he entered public life he voluntarily surrendered the privacy secured by law for those who elect not to place themselves in the public spotlight. See, e. g., New York Times Co. v. Sullivan, 376 U. S. 254 (1964). He argues, however, that he was not thereby stripped of all legal protection of his privacy, and contends that the Act violates fundamental rights of expression and privacy guaranteed to him by the First, Fourth, and Fifth Amendments.18
*456The District Court treated appellant’s argument as addressed only to the process by which the screening of the materials will be performed. “Since any claim by [appellant] that his privacy will be invaded by public access to private materials must be considered premature when it must actually be directed to the regulations once they become effective, we need not consider how the materials will be treated after they are reviewed.” 408 F. Supp., at 358. Although denominating the privacy claim “[t]he most troublesome challenge that plaintiff raises . . . ,” id., at 357, the District Court concluded that the claim was without merit. The court reasoned that the proportion of the 42 million pages of documents and 880 tape recordings implicating appellant’s privacy interests was quite small since the great bulk of the materials related to appellant’s conduct of his duties as President, and were therefore materials to which great public interest attached. The touchstone of the legality of the archival processing, in the District Court’s view, was its reasonableness. Balancing the public interest in preserving the materials touching appellant’s performance of his official duties against the invasion of appellant’s privacy that archival screening necessarily entails, the District Court concluded that the Act was not unreasonable and hence not facially unconstitutional:
“Here, we have a processing scheme without which national interests of overriding importance cannot be served . . . .” Id., at 364.
Thus, the Act “is a reasonable response to the difficult problem caused by the mingling of personal and private documents and conversations in the midst of a vastly greater number of nonprivate documents and materials related to government objectives. The processing contemplated by the Act — at least as narrowed by carefully tailored regulations— represents the least intrusive manner in which to provide an adequate level of promotion of government interests of over*457riding importance.” Id., at 367. We agree with the District Court that the Act does not unconstitutionally invade appellant’s right of privacy.
One element of privacy has been characterized as “the individual interest in avoiding disclosure of personal matters . . . .” Whalen v. Roe, 429 U. S. 589, 599 (1977). We may agree with appellant that, at least when Government intervention is at stake, public officials, including the President, are not wholly without constitutionally protected privacy rights in matters of personal life unrelated to any acts done by them in their public capacity. Presidents who have established Presidential libraries have usually withheld matters concerned with family or personal finances, or have deposited such materials with restrictions on their screening. 408 F. Supp., at 360.19 We may assume with the District *458Court, for the purposes of this case, that this pattern of de jacto Presidential control and congressional acquiescence gives rise to appellant’s legitimate expectation of privacy-in such materials. Katz v. United States, 389 U. S. 347, 351-353 (1967).20 This expectation is independent of the question of ownership of the materials, an issue we do not reach. See n. 8, supra. But the merit of appellant’s claim of invasion of his privacy cannot be considered in the abstract; rather, the claim must be considered in light of the specific provisions of the Act, and any intrusion must be weighed against the public interest in subjecting the Presidential materials of appellant’s administration to archival screening. Camara v. Municipal Court, 387 U. S. 523, 534— 539 (1967); Terry v. Ohio, 392 U. S. 1, 21 (1968).21 Under this test, the privacy interest asserted by appellant is weaker than that found wanting in the recent decision of Whalen v. Roe, supra. Emphasizing the precautions utilized by New York State to prevent the unwarranted disclosure of private medical information retained in a state computer bank system, Whalen rejected a constitutional objection to New York’s program on privacy grounds. Not only does the Act challenged here mandate regulations similarly aimed at preventing undue dissemination of private materials but, unlike Whalen, the Government will not even retain long-term control over *459such private information; rather, purely private papers and recordings will be returned to appellant under § 104 (a) (7) of the Act.
The overwhelming bulk of the 42 million pages of documents and the 880 tape recordings pertain, not to appellant’s private communications, but to the official conduct of his Presidency. Most of the 42 million pages were prepared and seen by others and were widely circulated within the Government. Appellant concedes that he saw no more than 200,000 items, and we do not understand him to suggest that his privacy claim extends to items he never saw. See United States v. Miller, 425 U. S. 435 (1976). Further, it is logical to assume that the tape recordings made in the Presidential offices primarily relate to the conduct and business of the Presidency. And, of course, appellant cannot assert any privacy claim as to the documents and tape recordings that he has already disclosed to the public. United States v. Dionisio, 410 U. S. 1, 14 (1973); Katz v. United States, supra, at 351. Therefore, appellant’s privacy claim embracing, for example, “extremely private communications between him and, among others, his wife, his daughters, his physician, lawyer, and clergyman, and his close friends, as well as personal diary dictabelts and his wife’s personal files,” 408 F. Supp., at 359, relates only to a very small fraction of the massive volume of official materials with which they are presently commingled.22
*460The fact that appellant may assert his privacy claim as to only a small fraction of the materials of his Presidency is plainly relevant in judging the reasonableness of the screening process contemplated by the Act, but this of course does not, without more, require rejection of his privacy argument. Id., at 359. Although the Act requires that the regulations promulgated by the Administrator under § 104 (a) take into account appellant’s legally and constitutionally based rights and privileges, presumably including his privacy rights, § 104 (a)(5), and also take into account the need to return to appellant his private materials, § 104(a)(7),23 the identity and separation of these purely private matters can be achieved, as all parties concede, only by screening all of the materials.
Appellant contends that the Act therefore is tantamount to a general warrant authorizing search and seizure of all of his Presidential “papers and effects.” Such “blanket authority,” appellant contends, is precisely the kind of abuse that the Fourth Amendment was intended to prevent, for “ 'the real evil aimed at by the Fourth Amendment is the search itself, that invasion of a man’s privacy which consists [in] rummaging about among his effects to secure evidence against him.’ ” Brief for Appellant 148, quoting United States v. Poller, 43 F. 2d 911, 914 (CA2 1930). Thus, his brief continues, at 150-151:
“[Appellant’s] most private thoughts and communications, both written and spoken, will be exposed to and reviewed by a host of persons whom he does not know and *461did not select, and in whom he has no reason to place his confidence. This group will decide what is personal, to be returned to [him], and what is historical, to be opened for public review.” 24
Appellant principally relies on Stanford v. Texas, 379 U. S. 476 (1965), but that reliance is misplaced. Stanford invalidated a search aimed at obtaining evidence that an individual had violated a “sweeping and many-faceted law which, among other things, outlaws the Communist Party and creates various individual criminal offenses, each punishable by imprisonment for up to 20 years.” Id., at 477. The search warrant authorized a search of his private home for books, records, and other materials concerning illegal Communist activities. After spending more than four hours in Stanford’s house, police officers seized half of his books which included works by Sartre, Marx, Pope John XXIII, Mr. Justice Hugo Black, Theodore Draper, and Earl Browder, as well as private documents including a marriage certificate, insurance policies, household bills and receipts, and personal correspondence. Id., at 479M80. Stanford held this to be an unconstitutional general search.
The District Court concluded that the Act’s provisions for *462custody and screening could not be analogized to a general search and that Stanford, therefore, did not require the Act’s invalidation. 408 F. Supp., at 366-367, n. 63. We agree. Only a few documents among the vast quantity of materials seized in Stanford were even remotely related to any legitimate government interest. This case presents precisely the opposite situation: the vast proportion of appellant’s Presidential materials are official documents or records in which appellant concedes the public has a recognized interest. Moreover, the Act provides procedures and orders the promulgation of regulations expressly for the purpose of minimizing the intrusion into appellant’s private and personal materials. Finally, the search in Stanford was an intrusion into an individual’s home to search and seize personal papers in furtherance of a criminal investigation and designed for exposure in a criminal trial. In contrast, any intrusion by archivists into appellant’s private papers and effects is undertaken with the sole purpose of separating private materials to be returned to appellant from nonprivate materials to be retained and preserved by the Government as a record of appellant’s Presidency.
Moreover, the screening will be undertaken by Government archivists with, as the District Court noted, “an unblemished record for discretion,” 408 F. Supp., at 365. That review can hardly differ materially from that contemplated by appellant’s intention to establish a Presidential library, for Presidents who have established such libraries have found that screening by professional archivists was essential. Although the District Court recognized that this contemplation of archival review would not defeat appellant’s expectation of privacy, the court held that it does indicate that “in the special situation of documents accumulated by a President during his tenure and reviewed by professional government personnel, pursuant to a process employed by past Presidents, any intrusion into privacy interests is less substantial than it might appear at first.” Ibid, (citation omitted).
*463The District Court analogized the screening process contemplated by the Act to electronic surveillance conducted pursuant to Title III of the Omnibus Crime Control and Safe Streets Act of 1968, 18 U. S. C. §§ 2510 et seq. 408 F. Supp., at 363. We think the analogy is apt. There are obvious similarities between the two procedures. Both involve the problem of separating intermingled communications, (1) some of which are expected to be related to legitimate Government objectives, (2) some of which are not, and (3) for which there is no means to segregate the one from the other except by reviewing them all. Thus the screening process under the Act, like electronic surveillance, requires some intrusion into private communications unconnected with any legitimate governmental objectives. Yet this fact has not been thought to render surveillance under the Omnibus Act unconstitutional. Cf., e. g., United States v. Donovan, 429 U. S. 413 (1977); Berger v. New York, 388 U S. 41 (1967).. See also 408 F. Supp., at 363-364.
Appellant argues that this analogy is inappropriate because the electronic surveillance procedure was carefully designed to meet the constitutional requirements enumerated in Berger v. New York, supra, including (1) prior judicial authorization, (2) specification of particular offenses said to justify the intrusion, (3) specification “with particularity” of the conversations sought to be seized, (4) minimization of the duration of the wiretap, (5) termination once the conversation sought is seized, and (6) a showing of exigent circumstances justifying use of the wiretap procedure. Brief for Appellant 157. Although the parallel is far from perfect, we agree with the District Court that many considerations supporting the constitutionality of the Omnibus Act also argue for the constitutionality of this Act’s materials screening process. For example, the Omnibus Act permits electronic surveillance only to investigate designated crimes that are serious in nature, 18 U. S. C. § 2516, and only when normal investigative techniques have failed or are likely to do so, §2518 (3)(c).' Similarly, *464the archival review procedure involved here is designed to serve important national interests asserted by Congress, and the unavailability of less restrictive means necessarily follows from the commingling of the documents.25 Similarly, just as the Omnibus Act expressly requires that interception of non-relevant communications be minimized, §2518 (5), the Act's screening process is designed to minimize any privacy intrusions, a goal that is further reinforced by regulations which must take those interests into account.26 The fact that apparently only a minute portion of the materials implicates appellant’s privacy interests27 also negates any conclusion that *465the screening process is an unreasonable solution to the problem of separating commingled communications.
In sum, appellant has a legitimate expectation of privacy in his personal communications. But the constitutionality of the Act must be viewed in the context of the limited intrusion of the screening process, of appellant’s status as a public figure, of his lack of any expectation of privacy in the overwhelming majority of the materials, of the important public interest in preservation of the materials, and of the virtual impossibility of segregating the small quantity of private materials without comprehensive screening. When this is combined with the Act’s sensitivity to appellant’s legitimate privacy interests, see § 104 (a) (7), the unblemished record of the archivists for discretion, and the likelihood that the regulations to be promulgated by the Administrator will further moot appellant’s fears that his materials will be reviewed by “a host of persons,” 28 Brief for Appellant 150, we are compelled to agree with the District Court that appellant’s privacy claim is without merit.
VI
First Amendment
During his Presidency appellant served also as head of his national political party and spent a substantial portion of *466his working time on partisan political matters. Records arising from his political activities, like his private and personal records, are not segregated from the great mass of materials. He argues that the Act’s archival screening process therefore necessarily entails invasion of his constitutionally protected rights of associational privacy and political speech. As summarized by the District Court: “It is alleged that the Act invades the private formulation of political thought critical to free speech and association, imposing sanctions upon past expressive activity, and more significantly, limiting that of the future because individuals who learn the substance of certain private communications by [appellant] — especially those critical of themselves — will refuse to associate with him. The Act is furthermore said to chill [his] expression because he will be 'saddled’ with prior positions communicated in private, leaving him unable to take inconsistent positions in the future.” 408 F. Supp., at 367-368.
The District Court, viewing these arguments as in essence a claim that disclosure of the materials violated appellant’s associational privacy, and therefore as not significantly different in structure from appellant’s privacy claim, again treated the arguments as limited to the constitutionality of the Act’s screening process. Id., at 368. As was true with respect to the more general privacy challenge, only a fraction of the materials can be said to raise a First Amendment claim. Nevertheless, the District Court acknowledged that appellant would “appear ... to have a legitimate expectation that he would have an opportunity to remove some of the sensitive political documents before any government screening took place.” Ibid. The District Court concluded, however, that there was no reason to believe that the mandated regulations when promulgated would not adequately protect against public access to materials implicating appellant’s privacy in political association, and that “any burden arising solely from review by professional and discreet archivists is not significant.” The court therefore held that the Act does not signifi*467cantly interfere with or chill appellant’s First Amendment rights. Id., at 369. We agree with the District Court’s conclusion.
It is, of course, true that involvement in partisan politics is closely protected by the First Amendment, Buckley v. Valeo, 424 U. S. 1 (1976), and that “compelled disclosure, in itself, can seriously infringe on privacy of association and belief guaranteed by the First Amendment.” Id., at 64. But a compelling public need that cannot be met in a less restrictive way will override those interests, Kusper v. Pontikes, 414 U. S. 51, 58-59 (1973); United States v. O’Brien, 391 U. S. 367, 376-377 (1968); Shelton v. Tucker, 364 U. S. 479, 488 (1960), “particularly when the 'free functioning of our national institutions’ is involved.” Buckley v. Valeo, supra, at 66. Since no less restrictive way than archival screening has been suggested as a means for identification of materials to be returned to appellant, the burden of that screening is presently the measure of his First Amendment claim. Id., at 84. The extent of any such burden, however, is speculative in light of the Act’s terms protecting appellant from improper public disclosures and guaranteeing him full judicial review before any public access is permitted. §§ 104 (a) (5), 104 (a) (7), 105 (a).29 As the District Court concluded, the First Amendment *468claim is clearly outweighed by the important governmental interests promoted by the Act.
For the same reasons, we find no merit in appellant’s argument that the Act’s scheme for custody and archival screening of the materials “necessarily inhibits [the] freedom of political activity [of future Presidents] and thereby reduces the ‘quantity and diversity’ of the political speech and association that the Nation will be receiving from its leaders.” Brief for Appellant 168. It is significant, moreover, that this concern has not deterred President Ford from signing the Act into law, or President Carter from urging this Court’s affirmance of the judgment of the District Court.
YII
Bill of Attainder Clause
A
Finally, we address appellant’s argument that the Act constitutes a bill of attainder proscribed by Art. I, § 9, of the Constitution.30 His argument is that Congress acted on the premise that he had engaged in “ ‘misconduct,’ ” was an “ ‘unreliable custodian’ ” of his own documents, and generally was deserving of a “legislative judgment of blameworthiness,” Brief for Appellant 132-133. Thus, he argues, the Act is pervaded with the key features of a bill of attainder: a law that legislatively determines guilt and inflicts punishment upon an identifiable individual without provision of the protections of a judicial trial. See United States v. Brown, 381 *469U. S. 437, 445, 447 (1965); United States v. Lovett, 328 U. S. 303, 315-316 (1946); Ex parte Garland, 4 Wall. 333, 377 (1867); Cummings v. Missouri, 4 Wall. 277, 323 (1867).
Appellant’s argument relies almost entirely upon United States v. Brown, supra, the Court’s most recent decision addressing the scope of the Bill of Attainder Clause. It is instructive, therefore, to sketch the broad outline of that case. Brown invalidated § 504 of the Labor-Management Reporting and Disclosure Act of 1959, 29 U. S. C. § 504, that made it a crime for a Communist Party member to serve as an officer of a labor union. After detailing the infamous history of bills of attainder, the Court found that the Bill of Attainder Clause was an important ingredient of the doctrine of “separation of powers,” one of the organizing principles of our system of government. 381 U. S., at 442-443. Just as Art. Ill confines the Judiciary to the task of adjudicating concrete “cases or controversies,” so too the Bill of Attainder Clause was found to “reflect. . . the Framers’ belief that the Legislative Branch is not so well suited as politically independent judges and juries to the task of ruling upon the blameworthiness of, and levying appropriate punishment upon, specific persons.” 381 U. S., at 445. Brown thus held that § 504 worked a bill of attainder by focusing upon easily identifiable members of a class — members of the Communist Party — and imposing on them the sanction of mandatory forfeiture of a job or office, long deemed to be punishment within the contemplation of the Bill of Attainder Clause. See, e. g., United States v. Lovett, supra, at 316; Cummings v. Missouri, supra, at 320.
Brown, Lovett, and earlier cases unquestionably gave broad and generous meaning to the constitutional protection against bills of attainder. But appellant’s proposed reading is far broader still. In essence, he argues that Brown establishes that the Constitution is offended whenever a law imposes undesired consequences on an individual or on a class *470that is not defined at a proper level of generality. The Act in question therefore is faulted for singling out appellant, as opposed to all other Presidents or members of the Government, for disfavored treatment.
Appellant’s characterization of the meaning of a bill of attainder obviously proves far too much. By arguing that an individual or defined group is attainted whenever he or it is compelled to bear burdens which the individual or group dislikes, appellant removes the anchor that ties the bill of attainder guarantee to realistic conceptions of classification and punishment. His view would cripple the very process of legislating, for any individual or group that is made the subject of adverse legislation can complain that the lawmakers could and should have defined the relevant affected class at a greater level of generality.31 Furthermore, every person or group made subject to legislation which he or it finds burdensome may subjectively feel, and can complain, that he or it is being subjected to unwarranted punishment. United States v. Lovett, supra, at 324 (Frankfurter, J., concurring).32 *471However expansive the prohibition against bills of attainder, it surely was not intended to serve as a variant of the equal protection doctrine,33 invalidating every Act of Congress or the States that legislatively burdens some persons or groups but not all other plausible individuals.34 In short, while the Bill of Attainder Clause serves as an important “bulwark against tyranny,” United States v. Brown, 381 U. S., at 443, it does not do so by limiting Congress to the choice of legislating for the universe, or legislating only benefits, or not legislating at all.
Thus, in the present case, the Act’s specificity — the fact that *472it refers to appellant by name — does not automatically offend the Bill of Attainder Clause. Indeed, viewed in context, the focus of the enactment can be fairly and rationally understood. It is true that Title I deals exclusively with appellant’s papers. But Title II casts a wider net by establishing a special commission to study and recommend appropriate legislation regarding the preservation of the records of future Presidents and all other federal officials. In this light, Congress’ action to preserve only appellant’s records is easily explained by the fact that at the time of the Act’s passage, only his materials demanded immediate attention. The Presidential papers of all former Presidents from Hoover to Johnson were already housed in functioning Presidential libraries. Congress had reason for concern solely with the preservation of appellant’s materials, for he alone had entered into a depository agreement, the Nixon-Sampson agreement, which by its terms called for the destruction of certain of the materials. Indeed, as the federal appellees argue, “appellant’s depository agreement . . . created an imminent danger that the tape recordings would be destroyed if appellant, who had contracted phlebitis, were to die.” Brief for Federal Appellees 41. In short, appellant constituted a legitimate class of one, and this provides a basis for Congress’ decision to proceed with dispatch with respect to his materials while accepting the status of his predecessors’ papers and ordering the further consideration of generalized standards to govern his successors.
Moreover, even if the specificity element were deemed to be satisfied here, the Bill of Attainder Clause would not automatically be implicated. Forbidden legislative punishment is not involved merely because the Act imposes burdensome consequences. Rather, we must inquire further whether Congress, by lodging appellant’s materials in the custody of the General Services Administration pending their screening by Government archivists and the promulgation of further regulations, “inflict [ed] punishment” within the constitu*473tional proscription against bills of attainder. United States v. Lovett, 328 U. S., at 315; see also United States v. Brown, supra, at 456-460; Cummings v. Missouri, 4 Wall., at 320.
B
1
The infamous history of bills of attainder is a useful starting point in the inquiry whether the Act fairly can be characterized as a form of punishment leveled against appellant. For the substantial experience of both England and the United States with such abuses of parliamentary and legislative power offers a ready checklist of deprivations and disabilities so disproportionately severe and so inappropriate to nonpuni-tive ends that they unquestionably have been held to fall within the proscription of Art. I; § 9. A statutory enactment that imposes any of those sanctions on named or identifiable individuals would be immediately constitutionally suspect.
In England a bill of attainder originally connoted a parliamentary Act sentencing a named individual or identifiable members of a group to death.35 Article I, § 9, however, also *474proscribes enactments originally characterized as bills of pains and penalties, that is, legislative Acts inflicting punishment other than execution. United States v. Lovett, supra, at 323-324 (Frankfurter, J., concurring); Cummings v. Missouri, supra, at 323; Z. Chafee, Jr., Three Human Rights in the Constitution of 1787, p. 97 (1956). Generally addressed to persons considered disloyal to the Crown or State, “pains and penalties” historically consisted of a wide array of punishments: commonly included were imprisonment,36 banishment,37 and the punitive confiscation of property by the sovereign.38 Our country’s own experience with bills of attainder resulted in the addition of another sanction to the list of impermissible legislative punishments: a legislative enactment barring designated individuals or groups from participation in specified employments or vocations, a mode of punishment commonly employed against those legislatively branded as disloyal. See, e. g., Cummings v. Missouri, supra (barring *475clergymen from ministry in the absence of subscribing to a loyalty oath); United States v. Lovett, supra (barring named individuals from Government employment); United States v. Brown, supra (barring Communist Party members from offices in labor unions).
Needless to say, appellant cannot claim to have suffered any of these forbidden deprivations at the hands of the Congress. While it is true that Congress ordered the General Services Administration to retain control over records that appellant claims as his property,39 § 105 of the Act makes provision for an award by the District Court of “just compensation.” This undercuts even a colorable contention that the Government has punitively confiscated appellant’s property, for the “owner [thereby] is to be put in the same position monetarily as he would have occupied if his property had not been taken.” United States v. Reynolds, 397 U. S. 14, 16 (1970); accord, United States v. Miller, 317 U. S. 369, 373 (1943). Thus, no feature of the challenged Act falls within the historical meaning of legislative punishment.
2
But our inquiry is not ended by the determination that the Act imposes no punishment traditionally judged to be prohibited by the Bill of Attainder Clause. Our treatment of the scope of the Clause has never precluded the possibility that new burdens and deprivations might be legislatively fashioned that are inconsistent with the bill of attainder guarantee. The Court, therefore, often has looked beyond mere historical experience and has applied a functional test of the existence of punishment, analyzing whether the law under challenge, viewed in terms of the type and severity of burdens imposed, reasonably can be said to further nonpunitive *476legislative purposes.40 Cummings v. Missouri, 4 Wall., at 319-320; Hawker v. New York, 170 U. S. 189, 193-194 (1898) ; Dent v. West Virginia, 129 U. S. 114, 128 (1889); Trop v. Dulles, 356 U. S. 86, 96-97 (1958) (plurality opinion); Kennedy v. Mendoza-Martines, 372 U. S. 144, 168-169 (1963). Where such legitimate legislative purposes do not appear, it is reasonable to conclude that punishment of individuals disadvantaged by the enactment was the purpose of the decisionmakers.
Application of the functional approach to this case leads to rejection of appellant’s argument that the Act rests upon a congressional determination of his blameworthiness and a desire to punish him. For, as noted previously, see supra, at 452-454, legitimate justifications for passage of the Act are readily apparent. First, in the face of the Nixon-Sampson agreement which expressly contemplated the destruction of some of appellant’s materials, Congress stressed the need to preserve “[ijnformation included in the materials of former President Nixon [that] is needed to complete the prosecutions *477of Watergate-related crimes.” H. R. Rep. No. 93-1507, p. 2 (1974). Second, again referring to the Nixon-Sampson agreement, Congress expressed its desire to safeguard the “public interest in gaining appropriate access to materials of the Nixon Presidency which are of general historical significance. The information in these materials will be of great value to the political health and vitality of the United States.” Ibid41 Indeed, these same objectives are stated in the text of the Act itself, § 104 (a), note following 44 U. S. C. § 2107 (1970 ed., Supp. V), where Congress instructs the General Services Administration to promulgate regulations that further these ends and at the same time protect the constitutional and legal rights of any individual adversely affected by the Administrator’s retention of appellant’s materials.
Evaluated in terms of these asserted purposes, the law plainly must be held to be an act of nonpunitive legislative policymaking. Legislation designed to guarantee the availability of evidence for use at criminal trials is a fair exercise of Congress’ responsibility to the “due process of law in the fair administration of criminal justice,” United States v. Nixon, 418 U. S., at 713, and to the functioning of our adversary legal system which depends upon the availability of relevant evidence in carrying out its commitments both to fair play and to the discovery of truth within the bounds set by law. Branzburg v. Hayes, 408 U. S. 665, 688 (1972); Blackmer v. United States, 284 U. S. 421, 438 (1932); Blair v. United States, 250 U. S. 273, 281 (1919). Similarly, Congress’ in*478terest in and expansive authority to act in preservation of monuments and records of historical value to our national heritage are fully established. United States v. Gettysburg Electric R. Co., 160 U. S. 668 (1896); Roe v. Kansas, 278 U. S. 191 (1929).42 A legislature thus acts responsibly in seeking to accomplish either of these objectives. Neither supports an implication of a legislative policy designed to inflict punishment on an individual.
3
A third recognized test of punishment is strictly a motivational one: inquiring whether the legislative record evinces a congressional intent to punish. See, e. g., United States v. Lovett, 328 U. S., at 308-314; Kennedy v. Mendoza-Martinez, supra, at 169-170. The District Court unequivocally found: “There is no evidence presented to us, nor is there any to be found in the legislative record, to indicate that Congress’ design was to impose, a penalty upon Mr. Nixon ... as punishment for alleged past wrongdoings.. . . The legislative history leads to only one conclusion, namely, that the Act before us is regulatory and not punitive in character.” 408 F. Supp., at 373 (emphasis omitted). We find no cogent reason for disagreeing with this conclusion.
First, both Senate and House Committee Reports, in formally explaining their reasons for urging passage of the Act, expressed no interest in punishing or penalizing appellant. Rather, the Reports justified the Act by reference to objectives that fairly and properly lie within Congress’ legislative competence: preserving the availability of judicial evidence and *479of historically relevant materials. Supra, at 476-478. More specifically, it seems clear that the actions of both Houses of Congress were predominantly precipitated by a resolve to undo the recently negotiated Nixon-Sampson agreement, the terms of which departed from the practice of former Presidents in that.they expressly contemplated the destruction of certain Presidential materials.43 Along these lines, H. R. Rep. No. 93-1507, supra, at 2, stated: “Despite the overriding public interest in preserving these materials . . . [the] Administrator of General Services entered into an agreement . . . which, if implemented, could seriously limit access to these records and . . . result in the destruction of a substantial portion of them.” See also S. Rep. No. 93-1181, p. 4 (1974). The relevant Committee Reports thus cast no aspersions on appellant's personal conduct and contain no condemnation of his behavior as meriting the infliction of punishment. Rather, they focus almost exclusively on the meaning and effect of an agreement recently announced by the General Services Administration which most Members of Congress perceived to be inconsistent with the public interest.
Nor do the floor debates on the measure suggest that Congress was intent on encroaching on the judicial function of punishing an individual for blameworthy offenses. When one of the opponents of the legislation, mischaracterizing the safeguards embodied in the bill,44 stated that it is “one which partakes of the characteristics of a bill of attainder . . . ,” 120 *480Cong. Rec. 33872 (1974) (Sen. Hruska), a key sponsor of the measure responded by expressly denying any intention of determining appellant’s blameworthiness or imposing punitive sanctions:
“This bill does not contain a word to the effect that Mr. Nixon is guilty of any violation of the law. It does not inflict any punishment on him. So it has no more relation to a bill of attainder .... than my style of pulchritude is to be compared to that of the Queen of Sheba.” Id., at 33959-33960 (Sen. Ervin).
In this respect, the Act stands in marked contrast to that invalidated in United States v. Lovett, 328 U. S., at 312, where a House Report expressly characterized individuals as “subversive . . . and . . . unfit ... to continue in Government employment.” H. R. Rep. No. 448, 78th Cong., 1st Sess., 6 (1943). We, of course, do not suggest that such a formal legislative announcement of moral blameworthiness or punishment is necessary to an unlawful bill of attainder. United States v. Lovett, supra, at 316. But the decided absence from the legislative history of any congressional sentiments expressive of this purpose is probative of nonpunitive intentions and largely undercuts a major concern that prompted the bill of attainder prohibition: the fear that the legislature, in seeking to pander to an inflamed popular constituency, will find it expedient openly to assume the mantle of judge — or, worse still, lynch mob. Cf. Z. Chafee, supra, at 161.45 No such legislative overreaching is involved here.
*481We also agree with the District Court that “specific aspects of the Act . . . just do not square with the claim that the Act was a punitive measure.” 408 F. Supp., at 373. Whereas appellant complains that the Act has for some two years deprived him of control over the materials in question, Brief for Appellant 140, the Congress placed the materials under the auspices of the General Services Administration, § 101, note following 44 U. S. C. §2107 (1970 ed., Supp. V), the same agency designated in the Nixon-Sampson agreement as depository of the documents for a minimum three-year period, App. 40. Whereas appellant complains that the Act deprives him of “ready access” to the materials, Brief for Appellant 140, the Act provides that “Richard M. Nixon, or any person whom he may designate in writing, shall at all times have access to the tape recordings and other materials .. . ,” § 102 (c).46 The District Court correctly construed this as safeguarding appellant’s right to inspect, copy, and use the materials in issue, 408 F. Supp., at 375, paralleling the right to “make reproductions” contained in the Nixon-Sampson agreement, App. 40. And even if we assume that there is merit in appellant’s complaint that his property has been confiscated, Brief for Appellant 140, the Act expressly provides for the payment of just compensation under § 105 (c); see supra, at 475.
Other features of the Act further belie any punitive interpretation. In promulgating regulations under the Act, the General Services Administration is expressly directed by Congress to protect appellant’s or “any party’s opportunity to assert any legally or constitutionally based right or privilege . . . .” § 104 (a)(5). More importantly, the Act preserves for appellant all of the protections that inhere in a judicial proceeding, for § 105 (a) not only assures district *482court jurisdiction and judicial review over all his legal claims, but commands that any such challenge asserted by appellant “shall have priority on the docket of such court over other cases.” A leading sponsor of the bill emphasized that this expedited treatment is expressly designed “to protect Mr. Nixon’s property, or other legal rights . . . .” 120 Cong. Rec. 33854 (1974) (Sen. Ervin). Finally, the Congress has ordered the General Services Administration to establish regulations that recognize “the need to give to Richard M. Nixon, or his heirs, for his sole custody and use, tape recordings and other materials which' are not likely to be related to” the articulated objectives of the Act, § 104 (a)(7). While appellant obviously is not set at ease by these precautions and safeguards, they confirm the soundness of the opinion given the Senate by the law division of the Congressional Research Service: “[Bjecause the proposed bill does not impose criminal penalties or other punishment, it would not appear to violate the Bill of Attainder Clause.” 120 Cong. Rec. 33853 (1974).47
One final consideration should be mentioned in light of the unique posture of this controversy. In determining whether a legislature sought to inflict punishment on an individual, it is often useful to inquire into the existence of less burdensome alternatives by which that legislature (here Congress) could have achieved its legitimate nonpunitive objectives. Today, in framing his challenge to the Act, appellant contends that such an alternative was readily available:
“If Congress had provided that the Attorney General or the Administrator of General Services could institute a civil suit in an appropriate federal court to enjoin disposi*483tion ... of presidential historical materials ... by any person who could be shown to be an 'unreliable custodian’ or who had 'engaged in misconduct’ or who 'would violate a criminal prohibition/ the statute would have left to judicial determination, after a fair proceeding, the factual allegations regarding Mr. Nixon’s blameworthiness.” Brief for Appellant 137.
We have no doubt that Congress might have selected this course. It very well may be, however, that Congress chose not to do so on the view that a full-fledged judicial inquiry into appellant’s conduct and reliability would be no less punitive and intrusive than the solution actually adopted. For Congress doubtless was well aware that just three months earlier, appellant had resisted efforts to subject himself and his records to the scrutiny of the Judicial Branch, United States v. Nixon, 418 U. S. 683 (1974), a position apparently maintained to this day.48 A rational and fairminded Congress, therefore, might well have decided that the carefully tailored law that it enacted would be less objectionable to appellant than the alternative that he today appears to endorse. To be sure, if the record were unambiguously to demonstrate that the Act represents the infliction of legislative punishment, the fact that the judicial alternative poses its own difficulties would be of no constitutional significance. But the record suggests the contrary, and the unique choice that Congress faced buttresses our conclusion that the Act cannot fairly be read to inflict legislative punishment as forbidden by the Constitution.
We, of course, are not blind to appellant’s plea that we *484recognize the social and political realities of 1974. It was a period of political turbulence unprecedented in our history. But this Court is not free to invalidate Acts of Congress based upon inferences that we may be asked to draw from our personalized reading of the contemporary scene or recent history. In judging the constitutionality of the Act, we may only look to its terms, to the intent expressed by Members of Congress who voted its passage, and to the existence or nonexistence of legitimate explanations for its apparent effect. We are persuaded that none of these factors is suggestive that the Act is a punitive bill of attainder, or otherwise facially unconstitutional. The judgment of the District Court is
Affirmed.
For proceedings prior to convention of the three-judge court, see Nixon v. Richey, 168 U. S. App. D. C. 169, 513 F. 2d 427, on reconsideration, 168 U. S. App. D. C. 172, 513 F. 2d 430 (1975). See also Nixon v. Sampson, 389 F. Supp. 107 (DC 1975).
No opinion was given respecting ownership of certain permanent files retained by the Chief Executive Clerk of the White House from administration to administration. The Attorney General was unable definitively to determine their status on the basis of then-available information. 43 Op. Atty. Gen. No. 1 (1974), App. 228.
The Court of Appeals for the District of Columbia Circuit stayed any order effectuating the decision in Nixon v. Sampson pending decision of the three-judge court whether under §105 (a) the instant case was to “have priority on the docket of [the District] court over other cases,” Nixon v. Richey, 168 U. S. App. D. C., at 173, 177, 188-190, 513 F. 2d, at 431, 435, 446-448. The three-judge court was of the view that “the central purpose of Congress, in relation to all pending litigation, is to have an early and prior determination of the Act’s constitutionality” and therefore did not request dissolution of the stay until entry of judgment. 408 F. Supp., at 333-334, n. 10.
This interpretation has abundant support in the legislative history of the Act. Senator Javits, one of the sponsors of S. 4016, stated:
“[The criteria of § 104 (a)] endeavor to protect due process for individ*437uals who may be named in the papers as well as any privilege which may be involved in the papers, and of course the necessary access of the former President himself.
“In short, the argument that the bill authorizes absolute unrestricted public access does not stand up in the face of the criteria and the requirement for the regulations which we have inserted in the bill today.” 120 Cong. Rec. 33860 (1974).
Senator Nelson, the bill’s draftsman, agreed that the primary purpose to provide for the American people a historical record of the Watergate events “should not override all regard for the rights of the individual to privacy and a fair trial.” Id., at 33851. Senator Ervin, also a sponsor and floor manager of the bill, stated:
“Nobody’s right is affected by this bill, because it provides, as far as privacy is concerned, that the regulations of the Administrator shall take into account . . . [the] opportunity to assert any legally or constitutionally based right which would prevent or otherwise limit access to the tape recordings and other materials.” Id., at 33969.
See also id., at 33960 (remarks of Sen. Ervin); id., at 37902-37903 (remarks of Rep. Brademas).
Madison in The Federalist No. 47, reviewing the origin of the separation-of-powers doctrine, remarked that Montesquieu, the “oracle” always consulted on the subject,
“did not mean that these departments ought to have no partial agency in, or no controul over the acts of each other. His meaning, as his own words import . . . can amount to no more than this, that where the whole power of one department is .exercised by the same hands which possess the whole power of another department, the fundamental principles of a free constitution, are subverted.” The Federalist No. 47, pp. 325-326 (J. Cooke ed. 1961) (emphasis in original).
Similarly, Mr. Justice Story wrote:
“[W]hen we speak of a separation of the three great departments of government, and maintain that that separation is indispensable to public liberty, we are to understand this maxim in a limited sense. It is not meant to affirm that they must be kept wholly and entirely separate and distinct, and have no common link of connection or dependence, the one upon the other, in the slightest degree.” 1 J. Story, Commentaries on the Constitution § 525 (M. Bigelow, 5th ed. 1905).
See also, e. g., 1 K. Davis, Administrative Law Treatise § 1.09 (1958); G. Gunther, Gases and Materials on Constitutional Law 400 (9th ed. 1975) ; L. Jaffe, Judicial Control of Administrative Action 28-30 (1965); Cox, Executive Privilege, 122 U. Pa. L. Rev. 1383, 1387-1391 (1974); Ratner, Executive Privilege, Self Incrimination, and the Separation of Powers Illusion, 22 UCLA L. Rev. 92-93 (1974).
The District Court correctly interpreted the Act to require meaningful notice to appellant of archival decisions that might bring into play rights secured by § 104 (a) (5). 408 F. Supp., at 340 n. 23. Such notice is required by the Administrator’s regulations, 41 CFR § 105-63.205 (1976), which provide: “The Administrator of General Services or his designated agent will provide former President Nixon or his designated attorney or agent prior notice of, and allow him to be present during, each authorized access.”
We see no reason to engage in the debate whether appellant has legal title to the materials. See Brief for Appellant 90. Such an inquiry is irrelevant for present purposes because § 105 (c) assures appellant of just compensation if his economic interests are invaded, and, even if legal title is his, the materials are not thereby immune from regulation. It has been accepted at least since Mr. Justice Story’s opinion in Folsom v. Marsh, 9 F. Cas. 342, 347 (No. 4, 901) (CC Mass. 1841), that regardless of where legal title lies, “from the nature of the public service, or the character of the documents, embracing historical, military, or diplomatic information, it may be the right, and even the duty, of the government, to give them publicity, even against the will of the writers.” Appellant’s suggestion that the Folsom principle does not go beyond materials concerning national security and current Government business is negated by Mr. Justice Story’s emphasis that it also extended to materials “embracing historical . . . information.” Ibid. (Emphasis added.) Significantly, no such limitation was suggested in the Attorney General’s opinion to President Ford. Although indicating a view that the materials belonged to appellant, the opinion acknowledged that “Presidential materials” without qualification “are peculiarly affected by a public interest” which may justify subjecting “the absolute ownership rights” to certain *446“limitations directly related to the character of the documents as records of government activity.” 43 Op. Atty. Gen. No. 1 (1974), App. 220-230.
On the other hand, even if legal title rests in the Government, appellant is not thereby foreclosed from asserting under § 105 (a) a claim for return of private materials retained by the Administrator in contravention of appellant’s rights and privileges as specified in § 104 (a) (5).
Like the District Court, we do not distinguish between the qualified “executive” privilege recognized in United States v. Nixon and the “Presidential” privilege to which appellant refers, except to note that appellant does not argue that the privilege he claims extends beyond the privilege recognized in that case. See 408 F. Supp., at 343 n. 24.
United States v. Nixon recognized that there is a legitimate governmental interest in the confidentiality of communications between high Government officials, e. g., those who advise the President, and that “[h]uman experience teaches that those who expect public dissemination *447of their remarks may well temper candor with a concern for appearances and for their own interests to the detriment of the decisionmaking process.” 418 U. S., at 705.
Indeed, the opinion noted, id., at 705 n. 15, that Government confidentiality has been a concern from the time of the Constitutional Convention in 1787, the meetings of which were conducted in private, 1 M. Farrand, The Records of the Federal Convention of 1787, pp. xi-xxv (1911), and the records of which were sealed for more than 30 years after the Convention. See 3 Stat. 475, 15th Cong., 1st Sess., Res. 8 (1818). See generally C. Warren, The Making of the Constitution 13U139 (1937).
The District Court found that in the Hoover Library there are no restrictions on Presidential papers, although some restrictions exist with respect to personal and private materials, and in the Roosevelt Library, less than 0.5% of the materials is restricted. There is no evidence in the record ■as to the percentage of materials currently under restriction in the Truman or Eisenhower Libraries, but in the Kennedy Library, 85% of the materials has been processed, and of the processed materials, only 0.6% is under donor (as distinguished from security-related) restriction. In the Johnson Library, review of nonclassified materials is virtually complete, and more than 99% of all nonsecurity classified materials is unrestricted. In each of the Presidential libraries, provision has been made for the removal of the restrictions with the passage of time. 408 F. Supp., at 346 n. 31.
Aside from the public access eventually to be provided under § 104, the Act mandates two other access routes to the materials. First, under § 102(b), access is available in accordance with lawful process served upon the Administrator. As we have noted, see n. 7, supra, the appellant is to be advised prior to any access to the materials, and he is thereafter free to review the specific materials at issue, see § 102 (c); 41 CFR § 105-63.301 (1976), in order to determine whether to assert any rights, privileges, or defenses. Section 102 (b) expressly conditions ultimate access by way of lawful process upon the right of appellant to invoke any rights, defenses, or privileges.
Second, § 102 (d) of the Act states: “Any agency or department in the executive branch of the Federal Government shall at all times have access to the tape recordings and other materials ... for lawful Government use . . . .” The District Court eschewed a broad reading of that section as permitting wholesale access by any executive official for any conceivable executive purpose. Instead, it construed § 102 (d) in light of Congress’ presumed intent that the Act operate within constitutional bounds — an intent manifested throughout the statute, see 408 F. Supp., at 337 n. 15. The District Court thus interpreted § 102(d), and in particular the phrase “lawful use,” as requiring that once appellant is notified of requested access by an executive official, see n. 7, supra, he be allowed to assert any constitutional right or privilege that in his view would bar access. See 408 F. Supp., at 338 n. 18. We agree with that interpretation.
From its exhaustive survey of the legislative history, the District Court concluded that the public interests served by the Act could be merged under “the rubric of preservation of an accurate and complete historical record.” Id., at 348-349.
S. Rep. No. 93-1181, pp. 3-5 (1974); H. R. Rep. No. 93-1507, p. 3 (1974); 120 Cong. Rec. 37904 (remarks of Rep. Abzug). See also § 102 (d) of the Act.
Presidents in the past have had to apply to the Presidential libraries of their predecessors for permission to examine records of past govern*453mental actions relating to current governmental problems. See 408 F. Supp., at 351-352. Although it appears that most such requests have been granted, Congress could legitimately conclude that the situation was unstable and ripe for change. It is clear from the face of the Act that making the materials available for the ongoing conduct of Presidential policy was at least one of the objectives of the Act. See § 102 (d).
S. Rep. No. 93-1181, pp. 1, 3 (1974); H. R. Rep. No. 93-1507, pp. 2-3, 8 (1974); Hearing on GSA Regulations Implementing Presidential Recordings and Materials Preservation Act before the Senate Committee on Government Operations, 94th Cong., 1st Sess., 256 (1975); 120 Cong. Rec. 31549-31550 (1974) (remarks of Sen. Nelson); id., at 33850-33851; id., at 33863 (remarks of Sen. Ervin); id., at 33874-33875 (remarks of Sen. Huddleston); id., at 33875-33876 (remarks of Sen. Ribieoff); id., at 33876 (remarks of Sen. Muskie); id., at 33964-33965 (remarks of Sen. Nelson); id., at 37900-37901 (remarks of Rep. Brademas). See also §§ 101 (b) (1), 104 (a) (7) of the Act.
As to these several objectives of the legislature, see S. Rep. No. 93-1181, pp. 1, 3-4, 6 (1974); H. R. Rep. No. 93-1507, pp. 2-3, 8 (1974) ; 120 Cong. Rec. 31549-31550 (1974) (remarks of Sen. Nelson); id., at 33849-33851; id., at 37900-37901 (remarks of Rep. Brademas); id., at 37905 (remarks of Rep. McKinney). See also §§ 102 (b), 104 (a) of the Act.
Insofar as appellant argues a privacy claim based upon the First Amendment, see Part VI, infra. In joining this part of the opinion, Mr. Justice Stewart adheres to his views on privacy as expressed in his concurring opinion in Whalen v. Roe, 429 U. S. 589, 607 (1977).
The District Court, 408 F. Supp., at 360 n. 54, surveyed evidence in the record respecting depository restrictions for all Presidents since President Hoover. It is unclear whether President Hoover actually excluded any of his personal and private materials from the scope of his gift, although his offer to deposit materials in a Presidential library reserved the right to do so. President Franklin D. Roosevelt also indicated his intention to select certain materials from his papers to be retained by his family. Because of his death, this function was performed by designated individuals and by his secretary. Again the record is unclear as to how many materials were removed. A number of personal documents deemed to be personal family correspondence were turned over to the Roosevelt family library in 1948, later returned to the official library in 1954^1955, and have been on loan to the family since then. It is unclear to what extent these materials were reviewed by the library personnel.
President Truman withheld from deposit the personal file maintained in the White House by his personal secretary. This file was deposited with the library upon his death in 1974, although the terms of his will excluded a small number of items determined by the executors of his will to pertain to personal or business affairs of the Truman family. President Eisenhower’s offer to deposit his Presidential materials excluded materials determined by him or his representative to be personal or private. President Kennedy’s materials deposited with GSA did not include certain *458materials relating to his private affairs, and some recordings of meetings involving President Kennedy, although physically stored in the Kennedy Library, have not yet been turned over to the library or reviewed by Govemmént archivists. President Johnson’s offer to deposit materials excluded items which he determined to be of special or private interest pertaining to personal or family affairs.
Even if prior Presidents had declined to assert their privacy interests in such materials, their failure to do so would not necessarily bind appellant, for privacy interests are not solely dependent for their constitutional protection upon established practice of governmental toleration.
We agree with the District Court that the Fourth Amendment’s warrant requirement is not involved. 408 F. Supp., at 361-362.
Some materials are still in appellant’s possession, as the Administrator has not yet attempted to act on his authority under § 101 (b) (1) to take custody of them. See Brief for Federal Appellees 4 n. 1. Moreover, the Solicitor General conceded at oral argument that there are certain purely private materials which “should be returned to [appellant] once . . identified.” Tr. of Oral Arg. 58-59. The District Court enjoined the Government from “processing, disclosing, inspecting, transferring, or otherwise disposing of any materials . . . which might fall within the coverage of . . . the . . . Act. . . .” 408 F. Supp., at 375. As the District Court’s stay is no longer in effect, the Government should now promptly disclaim any interest in materials conceded to be appellant’s purely private communications and deliver them to him.
The Solicitor 'General implied at oral argument that the requirement of the guidelines directing the Administrator to consider the need to return to appellant “for his sole custody and use . . . materials which are not [Watergate related] . . . and are not otherwise of general historical significance,” § 104 (a) (7), is further qualified by the requirement under §§ 102 (b) and 104(a)(5), that the regulations promulgated by the Administrator take into account the need to protect appellant’s rights, defenses, or privileges. Tr. of Oral Arg. 37-38.
Appellant argues that screening under the Act contrasts with the screening procedures followed by earlier Presidents who, “in donating materials to Presidential libraries, have been able ... to participate in the selection of persons who would review the materials for classification purposes.” Brief for Appellant 151 n. 68. We are unable to say that the record substantiates this assertion. The record is most complete with respect to President Johnson, who appears to have recommended the individual who was later selected as' Director of the Johnson Library, but seems not to have played any role in the selection of the archivists actually performing the day-to-day processing. 408 F. Supp., at 365 n. 60. Moreover, we agree with the District Court that it is difficult to see how professional archivists performing a screening task under proper standards would be meaningfully affected in the performance of their duties by loyalty to individuals or institutions. Ibid.
Appellant argues that, unlike electronic surveillance, where success depends upon the subject’s ignorance of its existence, appellant could have been allowed to separate his personal from official materials. But Congress enacted the Act in part to displace the Nixon-Sampson agreement that expressly provided for automatic destruction of the tape recordings in the event of appellant’s death and that allowed appellant complete discretion in the destruction of materials after the initial three-year storage period.
Moreover, appellant’s view of what constitutes official as distinguished from personal and private materials might differ from the view of Congress, the Executive Branch, or a reviewing court. Not only may the use of disinterested archivists lead to application of uniform standards in separating private from nonprivate communications, but the Act provides for judicial review of their determinations. This would not be the case as to appellant’s determinations.
The District Court found, 408 F. Supp., at 364 n. 68, and we agree, that it is irrelevant that Title III, unlike this Act, requires adherence to a detailed warrant requirement, 18 U. S. C. § 2518. That requirement is inapplicable to this Act, since we deal not with standards governing a generalized right to search by law enforcement officials or other Government personnel but with a particularized legislative judgment, supplemented by judicial review, similar to condemnation under the power of eminent domain, that certain materials are of value to the public.
The fact that the overwhelming majority of the materials is relevant to Congress’ lawful objectives is in contrast to the experience under the Omnibus Crime Control Act. A recent report on surveillance conducted under the Omnibus Act indicates that for the calendar year 1976 more than one-half of all wire intercepts authorized by judicial order *465yielded only nonincriminating communications. Administrative Office of the U. S. Courts, Report on Applications for Orders Authorizing or Approving the Interception of Wire or Oral Communications, Jan. 1, 1976, to Dec. 31, 1976, p. XII (Table 4).
Throughout this litigation appellant has claimed that his privacy will necessarily be unconstitutionally invaded because the screening requires a staff of “over one hundred archivists, accompanied by lawyers, technicians and secretaries [who] will have a right to review word-by-word five and one-half years of a man’s life . . . .” Tr. of Oral Arg. 16. The size of the staff is, of course, necessarily a function of the enormous quantity of materials involved. But clearly not all engaged in the screening will examine each document. The Administrator initially proposed that only one archivist examine most documents. See 408 F. Supp., at 365 n. 59.
Appellant argues that Shuttlesworth v. Birmingham, 394 U. S. 147, 150-151 (1969); Cox v. Louisiana, 379 U. S. 536 (1965); Staub v. Baxley, 355 U. S. 313, 319-321 (1958); Thomas v. Collins, 323 U. S. 516, 538-541 (1945); and Lovell v. Griffin, 303 U. S. 444, 452-453 (1938), support his contention that “[a] statute which vests such broad authority [with respect to First Amendment rights] is unconstitutional on its face, and the party subjected to it may treat it as a nullity even if its actual implementation would, not harm him.” Brief for Appellant 169. The argument is without merit. Those cases involved regulations that permitted public officials in their arbitrary discretion to impose prior restraints on expressional or associational activities. In contrast, the Act is concerned only with materials that record past activities and with a screening process guided by longstanding archival screening standards.
Article I, §9, applicable to Congress, provides that “[n]o Bill of Attainder or ex post facto Law shall be passed,” and Art. I, § 10, applicable to the States, provides that “[n]o State shall . . . pass any Bill of Attainder, ex post facto Law . . . The linking of bills of attainder and ex post facto laws is explained by the fact that a legislative denunciation and condemnation of an individual often acted to impose retroactive punishment. See Z. Chafee, Jr., Three Human Rights in the Constitution of 1787, pp. 92-93 (1956).
In this case, for example, appellant faults the Act for taking custody of his papers but not those of other Presidents. Brief for Appellant 130. But even a congressional definition of the class consisting of all Presidents would have been vulnerable to the claim of being overly specific, since the definition might more generally include all members of the Executive Branch, or all members of the Government, or all in possession of Presidential papers, or all in possession of Government papers. This does not dispose of appellant’s contention that the Act focuses upon him with the requisite degree of specificity for a bill of attainder, see infra, at 471-472, but it demonstrates that simple reference to the breadth of the Act’s focus cannot be determinative of the reach of the Bill of Attainder Clause as a limitation upon legislative action that disadvantages a person or group. See, e. g., United States v. Brown, 381 U. S. 437, 474-475 (1965) (White, J., dissenting); n. 34, infra.
“The fact that harm is inflicted by governmental authority does not make it punishment. Figuratively speaking all discomforting action may be deemed punishment because it deprives of what otherwise would be enjoyed. But there may be reasons other than punitive for such deprivation.”
We observe that appellant originally argued that “for similar reasons” the Act violates both the Bill of Attainder Clause and equal protection of the laws. Jurisdictional Statement 27-28. He has since abandoned reliance upon the equal protection argument, apparently recognizing that mere underinclusiveness is not fatal to the validity of a law under the equal protection component of the Fifth Amendment, New Orleans v. Dukes, 427 U. S. 297 (1976); Katzenbach v. Morgan, 384 U. S. 641, 657 (1966), even if the law disadvantages an individual or identifiable members of a group, see, e. g., Williamson v. Lee Optical Co., 348 U. S. 483 (1955) (opticians); Daniel v. Family Ins. Co., 336 U. S. 220 (1949) (insurance agents). “For similar reasons” the mere specificity of a law does not call into play the Bill of Attainder Clause. Cf. Comment, The Supreme Court’s Bill of Attainder Doctrine: A Need for Clarification, 54 Calif. L. Rev. 212, 234-236 (1966); but see Comment, The Bounds of Legislative Specification: A Suggested Approach to the Bill of Attainder Clause, 72 Yale L. J. 330 (1962).
Brown recognized this by making clear that conflict-of-interest laws, which inevitably prohibit conduct on the part of designated individuals or classes of individuals, do not contravene the bill of attainder guarantee. Brown specifically noted the validity of § 32 of the Banking Act of 1933, 12 U. S. C. §78, which disqualified identifiable members of a group — officers and employees of underwriting organizations — from serving as officers of Federal Reserve banks, 381 U. S., at 453. Other valid federal conflict-of-interest statutes which also single out identifiable members of groups to bear burdens or disqualifications are collected, id., at 467-468, n. 2 (White, J., dissenting). See also Regional Rail Reorganization Act Cases, 419 U. S. 102 (1974) (upholding transfer of rail properties of eight railroad companies to Government-organized corporation).
See, for example, the 1685 attainder of James, Duke of Monmouth, for high treason: “WHEREAS James duke of Monmouth has in an hostile manner invaded this kingdom, and is now in open rebellion, levying war against the Idng, contrary to the duty of his allegiance; Be it enacted by the King’s most excellent majesty, by and with the advice and consent of the lords spiritual and temporal,, and commons in this parliament assembled, and by the authority of the same, That the said James duke of Monmouth stand and be convicted and attainted of high treason, and that he suffer pains of death, and incur all forfeitures as a traitor convicted and attainted of high treason.” 1 Jac. 2, c. 2 (1685) (emphasis omitted).
The attainder of death was usually accompanied by a forfeiture of the condemned person’s property to the King and the corruption of his blood, whereby his heirs were denied the right to inherit his estate. Blackstone traced the practice of “corruption of blood” to the Norman conquest He considered the practice an “oppressive mark of feudal *474tenure” and hoped that it “may in process of time be abolished by act of parliament.” 4 W. Blackstone Commentaries *388. The Framers of the United States Constitution responded to this recommendation. Art. HI, §3.
See, e. g., 10 & 11 Will. 3, c. 13 (1701): “An Act for continuing the Imprisonment of Counter and others, for the late horrid Conspiracy to assassinate the Person of his sacred Majesty.”
See, e. g., Cooper v. Telfair, 4 Dali. 14 (1800) (“‘all and every the persons, named and included in the said act [declaring persons guilty of treason] are banished from the said state [Georgia] ”’); 2 R. Woodde-son, A Systematical View of the Laws of England 638-639 (1792) (banishment of Lord Clarendon and the Bishop Atterbury). See Kennedy v. Mendoza-Martinez, 372 U. S. 144, 168, n. 23 (1963).
Following the Revolutionary War, States often seized the property of alleged Tory sympathizers. See, e. g., James’s Claim, 1 Dali. 47 (1780) (“John Parrock was attainted of High Treason, and his estate seized and advertised for sale”); Respublica v. Gordon, 1 Dall. 233 (1788) (“at-tainted of treason for adhering to the king of Great Britain, in consequence of which his estate was confiscated to the use of the commonwealth . . .”).
In fact, it remains unsettled whether the materials in question are the property of appellant or of the Government. See n. 8, swpra.
In determining whether punitive or nonpunitive objectives underlie a law, United States v. Brown established that punishment is not restricted purely to retribution for past events, but may include inflicting deprivations on some blameworthy or tainted individual in order to prevent his future misconduct. 381 U. S., at 458-459. This view is consistent with the traditional purposes of criminal punishment, which also include a preventive aspect. See, e. g., H. Packer, The Limits of the Criminal Sanction 48-61 (1968). In Brown the element of punishment was found in the fact that “the purpose of the statute before us is to purge the governing boards of labor unions of those whom Congress regards as guilty of subversive acts and associations and therefore unfit to fill [union] positions . . . .” 381 U. S., at 460. Thus, Brown left undisturbed the requirement that one who complains of being attainted must establish that the legislature’s action constituted punishment and not merely the legitimate regulation of conduct. Indeed, just three Terms later, United States v. O’Brien, 391 U. S. 367, 383 n. 30 (1968), which, like Brown, was also written by Mr. Chief Justice Warren, reconfirmed the need to examine the purposes served by a purported bill of attainder in determining whether it in fact represents a punitive law.
The Senate pointed to these same objectives in nullifying the Nixon-Sampson agreement: “[1] To begin with, prosecutors, defendants, and the courts probably would be deprived of crucial evidence bearing on the defendants’ innocence or guilt of the Watergate crimes for which they stand accused. [2] Moreover, the American people would be denied full access to all facts about the Watergate affair, and the efforts of Congress, the executive branch, and others to take measures to prevent a recurrence of the Watergate affair may be inhibited.” S. Rep. No. 93-1181, p. 4 (1974).
These cases upheld exercises of the power of eminent domain in preserving historical monuments and like facilities for public use. The power of eminent domain, however, is not restricted to tangible property or realty but extends both to intangibles and to personal effects as involved here. See Cincinnati v. Louisville & Nashville R. Co., 223 U. S. 390, 400 (1912); Porter v. United States, 473 F. 2d 1329 (CA5 1973).
Particularly troublesome was the provision of the agreement requiring the automatic destruction of tape recordings upon appellant’s death.
In condemning the enactment as a bill of attainder, Senator Hruska argued that the bill seizes appellant’s papers and distributes them to litigants without affording appellant the opportunity judicially “to assert a defense or privilege to the production of the papers.” 120 Cong. Rec. 33871 (1974). In fact, the Act expressly recognizes appellant’s right to present all such defenses and privileges through an expedited judicial proceeding. See infra, at 481-482.
The Court in United States v. Brown, 381 U. S., at 444, referred to Alexander Hamilton’s concern that legislatures might cater to the “momentary passions” of a “'free people, in times of heat and violence In this case, it is obvious that the supporters of this Act steadfastly avoided inflaming or appealing to any “passions” in the community. Indeed, rather than seek expediently to impose punishment and to circumvent the courts, Congress expressly provided for access to the Judiciary for resolution of any constitutional and legal rights appellant might assert. S. Rep. No. 93-1181, pp. 2-6 (1974).
Regulations guaranteeing appellant’s unrestricted access to the materials have been promulgated by the Administrator and have not been challenged. See 41 CFR § 105-63.3 (1976).
In brief, the legislative history of the Act offers a paradigm of a Congress aware of constitutional constraints on its power and carefully seeking to act within those limitations. See generally Brest, The Conscientious Legislator’s Guide to Constitutional Interpretation, 27 Stan. L. Rev. 685 (1975).
For example, in his deposition taken in this case, appellant refused to answer questions pertaining to the accuracy and reliability of his prior public statements as President concerning the contents of the tape recordings and other materials in issue. He invoked a claim of privilege and asserted that the questions were irrelevant to the judicial inquiry. See, e. g., App. 586-590.