JUSTICE STEVENS delivered the opinion of the Court.The Attorney General of Illinois asserts a statutory right of access to transcripts, documents, and other materials gathered Page 460 U. S. 560 or generated by two federal grand juries during their investigations of alleged violations of the federal antitrust laws.  He contends that § 4F(b) of the Clayton Act, 90 Stat. 1395, 15 U.S.C. § 15f(b), enacted as part of Title III of the Hart-Scott-Rodino Antitrust Improvements Act of 1976 (Act), makes it unnecessary for him to meet the "particularized need" standard generally required under Rule 6(e) of the Federal Rules of Criminal Procedure in order to obtain access to grand jury materials.  Disagreeing with two other Page 460 U. S. 561 Courts of Appeals, [Footnote 1] the Seventh Circuit rejected this contention.  We granted certiorari to resolve the conflict, 455 U.S. 1015 (1982), and now affirm.IOn January 31, 1980, the State of Illinois filed a petition in the United States District Court for the Northern District of Illinois seeking disclosure of transcripts and documents generated during two federal grand jury investigations of alleged bid-rigging in the construction trades in Illinois.  These investigations had resulted in the return of three separate indictments naming 59 defendants. [Footnote 2]  At the time the State filed its petition, most of the defendants had entered pleas of nolo contendere to the federal charges and one had been found guilty by a jury, but eight defendants were still awaiting trial. [Footnote 3]  The Justice Department had refused the State's request for the grand jury materials, [Footnote 4] explaining that they Page 460 U. S. 562 could not be disclosed without a court order under Rule 6(e) of the Federal Rules of Criminal Procedure. [Footnote 5]The State advised the District Court that it had already initiated civil class actions against 86 defendants, charged in the indictments or identified as unindicted coconspirators, to recover damages based on federal antitrust violations.  The State's petition invoked § 4F(b) [Footnote 6] and Rule 6(e) in support of Page 460 U. S. 563 disclosure.  It further stated that"the materials requested are extremely relevant and material to Plaintiff's causes; their disclosure will insure and promote efficient and economical utilization of scarce judicial and taxpayers resources, and will also obviate the need for duplicative and redundant discovery. . . ."App. 13.  The Department of Justice supported the State's petition. [Footnote 7]  Certain defendants in the civil suits and others who had testified before the grand juries intervened to oppose disclosure.The District Court first considered the State's claim that it had a statutory right of access under § 4F(b) without making any showing of compelling or particularized need.  The court concluded that, in response to a § 4F(b) request, the Justice Department was free to disclose documents that were independently acquired by the Executive Branch and voluntarily presented to the grand jury.  But it held that transcripts of grand jury testimony and other materials acquired by the grand jury through the use of its subpoena power were not part of the "investigative files" of the Attorney General of the United States within the meaning of the Act.  Moreover, the court found nothing in the legislative history of the Act to suggest that Congress intended either to authorize "unmonitored Page 460 U. S. 564 disclosure of purely grand jury materials" without a court order under Rule 6(e), or to modify the standard traditionally applied under Rule 6(e) itself.The District Court then explained why the record as then developed would not justify disclosure under Rule 6(e) without reference to § 4F(b).  Noting the absence of any special showing of need for access to the grand jury materials, the scope of the material otherwise available to the plaintiffs, and the interests in grand jury secrecy that survived the termination of criminal proceedings, [Footnote 8] the District Court denied all of the petitions for disclosure.  The denial, however, was without prejudice to renewed requests under Rule 6(e) after discovery efforts created a basis for more narrowly focused requests showing "particularized needs." [Footnote 9] Page 460 U. S. 565The State of Illinois filed a timely appeal to the United States Court of Appeals for the Seventh Circuit.  On appeal, the State did not contend that its petition had satisfied the showing of particularized need normally required under Rule 6(e).  Instead, it presented the issue that had been finally resolved by the District Court's order:  whether § 4F(b) gives the state attorney general a special right of access to grand jury materials that is independent of or that modifies the limitations that were imposed by Rule 6(e) in 1976 when the Act became law.  Noting that the plain language of the Act authorizes disclosure only "to the extent permitted by law," and that the legislative history affirmatively indicates Congress' intent to preserve then-existing limitations on access to grand jury materials, the Court of Appeals affirmed.  In re Illinois Petition to Inspect and Copy Grand Jury Materials, 659 F.2d 800 (1981).IISection 4F(a) of the Clayton Act, 15 U.S.C. § 15f(a), provides that, whenever the Attorney General of the United States has brought an action under the antitrust laws, and he has reason to believe that any state attorney general would be entitled to bring a federal action based substantially on the same alleged violation, he shall promptly give written notification to that official.  Under § 4F(b), 15 U.S.C. § 15f(b), in order to assist a state attorney general in evaluating this Page 460 U. S. 566 notice or in bringing an action, the Attorney General of the United States"shall, upon request by such State attorney general, make available to him, to the extent permitted by law, any investigative files or other materials which are or may be relevant or material to the actual or potential cause of action under this Act."The plain language of § 4F(b) requires us to evaluate the legal context in which Congress legislated in 1976.  The statute expressly mandates disclosure of investigative files and other materials only "to the extent permitted by law."  It is therefore appropriate to examine the extent to which, at the time the Act was passed, federal law permitted the Attorney General of the United States to disclose matters occurring before a federal grand jury to a state attorney general. [Footnote 10]Since 1946, the disclosure of grand jury minutes has been governed by Rule 6(e) of the Federal Rules of Criminal Procedure.  In so many words, the Rule establishes a "General Rule of Secrecy," a knowing violation of which "may be punished as a contempt of court." [Footnote 11]  The Rule provides that Page 460 U. S. 567 grand jury transcripts shall remain in the custody of the attorney for the Government "unless otherwise ordered by the court in a particular case." [Footnote 12]  There is only one exception to the general prohibition against disclosure without prior court approval, but that exception is limited to Federal Government personnel performing a specified federal law enforcement function. [Footnote 13]  Plainly Rule 6(e) does not permit the Attorney General of the United States to disclose any grand jury proceedings to a state attorney general unless he is directed to do so by a court.The court, however, is authorized by Rule 6(e)(3)(C) to permit certain disclosures that are otherwise prohibited by the "General Rule of Secrecy."  The scope of that authority has been delineated in a series of cases setting forth the standard of "particularized need." [Footnote 14]  We need not delineate the precise contours of that standard in this case, because the State made no attempt to make any such showing in the District Court, see n 8, supra, and has consistently maintained that it need not shoulder that burden. [Footnote 15] Page 460 U. S. 568Thus, under the law as it existed in 1976, two propositions were clear:  (1) a state attorney general could not obtain access to federal grand jury proceedings without federal court approval; and (2) the State could not secure such approval merely by alleging that the materials were relevant to an actual or potential civil antitrust action. [Footnote 16]  At the time the Act was passed in 1976, a blanket disclosure request comparable to the one at issue in this case would have been denied, because it was not permitted by law.  The State does not suggest that there has been any change in the law since 1976 that affects its right to disclosure. [Footnote 17]  It therefore follows from the plain language of the Act that the State Attorney General is not entitled to the disclosure he seeks in this case.IIIIf the text of § 4F(b) left any doubt concerning its recognition of the "General Rule of Secrecy" for grand jury materials, Page 460 U. S. 569 that doubt would be removed by its legislative history.  First, Congress considered and rejected a proposed section that would have specifically granted civil antitrust plaintiffs a right of access to grand jury materials after completion of federal civil or criminal proceedings.  As reported by the Senate Judiciary Committee, the provision eliminated the particularized need requirement and permitted disclosure, subject to court-imposed conditions, upon payment of reasonable costs. [Footnote 18]  The proposed sweeping invasion of grand jury secrecy drew substantial criticism from a number of Senators. [Footnote 19]  A floor amendment limited the section's scope, and, as amended, it was adopted by the Senate, [Footnote 20] but at the informal House-Senate conference, the House conferees objected and the Senate's provision was dropped. [Footnote 21]  The net effect of these Page 460 U. S. 570 deliberations was to leave the law applicable to grand jury materials unchanged.Second, a specific explanation of § 4F(b) by Senator.Abourezk, the floor manager of the legislation, confirms the conclusion that Congress did not intend to change existing law concerning grand jury materials.  The section was included in the compromise bill accepted by an informal House-Senate conference.  After Senator Hruska expressed his concern that § 4F(b) might require the Department of Justice to act as "a massive document distribution center for the benefit of State officials," [Footnote 22] Senator Abourezk explained:"The section specifically limits the Attorney General's power to release documents to whatever his powers are under existing law.  Under existing law, he cannot turn over materials given in response to a grand jury demand or to a civil investigative demand.  Therefore, the section is limited by existing law to cases where materials were turned over voluntarily."122 Cong.Rec. 29160 (1976).  Senator Abourezk's interpretation of this provision was not questioned. [Footnote 23] Page 460 U. S. 571Third, the Act's treatment of material obtained by the Government in response to Civil Investigative Demands (CID's) supports our interpretation of § 4F(b).  The Act increases the Attorney General's CID powers, [Footnote 24] but mandates that materials obtained in this manner be kept strictly confidential.  CID materials may not be disclosed to persons outside the Federal Government without the consent of the provider.  15 U.S.C. § 1313 (1976 ed. and Supp. V).  This requirement was imposed to safeguard the rights of individuals under investigation and to protect witnesses from retaliation. [Footnote 25]  Since those reasons also underlie the traditional secrecy accorded to the grand jury, it would be anomalous for the same Congress that placed stringent limits on CID materials silently to have abrogated grand jury secrecy by permitting wholesale disclosure. [Footnote 26] Page 460 U. S. 572IVFinally, the State argues that the Act implements a general policy of encouraging federal/state cooperation and giving state attorneys general an important role in the enforcement of the antitrust laws.  According to the State, this broad legislative goal would be served by facilitating the State's access to grand jury materials.  The State contends that virtually all of the Federal Government's investigations of core Sherman Act violations -- such as price-fixing and bid-rigging -- are conducted from the outset by means of grand juries. [Footnote 27]  Therefore, as in this case, a narrow reading of § 4F(b) would severely limit the amount of additional disclosure to state attorneys general.  Further, the State asserts, a "particularized need" standard would be difficult to satisfy before a State has filed a civil action and attempted civil discovery -- a stage when § 4F(b) is intended to provide assistance to the State.However correct these assertions may be, they do not authorize us to add specific language that Congress did not include in a carefully considered statute.  Congress, of course, has the power to modify the rule of secrecy by changing the showing of need required for particular categories of litigants. [Footnote 28]  But the rule is so important, and so deeply rooted in our traditions, that we will not infer that Congress has exercised Page 460 U. S. 573 such a power without affirmatively expressing its intent to do so.  The general goals of enhancing federal-state cooperation in antitrust enforcement, and encouraging more state lawsuits against price fixers, are not sufficient. [Footnote 29]  The statute as enacted by Congress simply does not authorize the Attorney General to turn over the entire investigative record of a federal antitrust grand jury to a state attorney general who has not complied with the judicially developed standards implementing Rule 6(e).  Because the disclosure requested by the State in this case is not permitted by Rule 6(e) on the basis of the showing it made to the District Court, the judgment of the Court of Appeals is affirmed.It is so ordered
U.S. Supreme CourtIllinois v. Abbott & Assocs., Inc., 460 U.S. 557 (1983)Illinois v. Abbott & Assocs., Inc.No. 81-1114Argued November 29, 1982Decided March 29, 1983460 U.S. 557SyllabusSection 4F(a) of the Clayton Act, enacted in 1976, provides that, whenever the Attorney General of the United States has brought an action under the federal antitrust laws and has reason to believe that any state attorney general would be entitled to bring an action under the Act based on substantially the same alleged violation, he shall give written notification to that official.  Under § 4F(b), in order to assist a state attorney general in evaluating this notice or in bringing an action, the United States Attorney General, upon the state attorney general's request, must make available to him,"to the extent permitted by law, any investigative files or other materials which are or may be relevant or material to the actual or potential cause of action"under the Act.  After the Justice Department had refused the State of Illinois' request for certain grand jury materials involved in an investigation of alleged violations of the federal antitrust laws, the Attorney General of Illinois filed a petition in Federal District Court asserting a right of access to such materials, and contending that § 4F(b) made it unnecessary for him to meet the "particularized need" standard required under Federal Rule of Criminal Procedure 6(e).  The District Court denied the petition, and the Court of Appeals affirmed.Held:  Section 4F(b) does not give the state attorney general a special right of access to grand jury materials that is independent of or modifies the limitations imposed by Rule 6(e).  Pp.  460 U. S. 565-573.(a) Rule 6(e) establishes a "General Rule of Secrecy" by providing that grand jury transcripts shall remain in the custody of the attorney for the Federal Government "unless otherwise ordered by the court in a particular case."  One seeking disclosure under Rule 6(e) is normally required to make a showing of a "particularized need" in order to obtain access to grand jury materials.  Under that Rule, a state attorney general cannot obtain access to federal grand jury proceedings without federal court approval, and such approval cannot be obtained merely by alleging that the materials are relevant to an actual or potential civil antitrust action.  Accordingly, it follows from the language of § 4F(b) mandating disclosure of investigative files and other materials only "to Page 460 U. S. 558 the extent permitted by law," that the Illinois Attorney General is not entitled to the disclosure sought in this case.  Pp.  460 U. S. 565-568.(b) Section 4F(b)'s legislative history supports the conclusion that Congress intended the section to recognize the "General Rule of Secrecy," and did not intend to change applicable law concerning grand jury materials.  Pp.  460 U. S. 568-571.(c) The Act's general goals of enhancing federal-state cooperation and encouraging more state lawsuits against price-fixers are not sufficient to show that Congress intended to change existing rules of law, absent an affirmative expression of intent to do so.  Pp.  460 U. S. 572-573.659 F.2d 800, affirmed.STEVENS, J., delivered the opinion for a unanimous Court.  BRENNAN, J., filed a concurring opinion, in which O'CONNOR, J., joined., post, p.  460 U. S. 573. Page 460 U. S. 559