Me. Chief Justice Buegee
delivered the opinion of the Court.
This direct appeal from the District Court presents the question whether a Member of Congress may be prosecuted under 18 U. S. C. §§201 (c)(1), 201(g), for accepting a bribe in exchange for a promise relating to an official act. Appellee, a former United States Senator, was charged in five counts of a 10-count indictment.1 Counts one, three, five, and seven alleged that on four separate occasions, appellee, while he was a Senator and a member of the Senate Committee on Post Office and Civil Service,
“directly and indirectly, corruptly asked, solicited, sought, accepted, received and agreed to receive [sums] ... in return for being influenced in his performance of official acts in respect to his action, vote, and decision on postage rate legislation which might at any time be pending before him in his official capacity ... in violation of Sections 201 (c)(1) and 2, Title 18, United States Code.”2
[503]*503Count nine charged that appellee
“directly and indirectly, asked, demanded, exacted, solicited, sought, accepted, received and agreed to receive [a sum] ... for and because of official acts performed by him in respect to his action, vote and decision on postage rate legislation which had been pending before him in his official capacity .. . in violation of Sections 201 (g) and 2, Title 18, United States Code.”3
Before a trial date was set, the appellee moved to dismiss the indictment on the ground of immunity under the Speech or Debate Clause, Art. I, § 6, of the Constitution, which provides:
“[F]or any Speech or Debate in either House, they [Senators or Representatives] shall not be questioned in any other Place.”
After hearing argument, the District Court ruled from the bench:
“Gentlemen, based on the facts of this case, [504]*504it is admitted by the Government that the five counts of the indictment which charge Senator Brewster relate to the acceptance of bribes in connection with the performance of a legislative function by a Senator of the United' States.
“It is the opinion of this Court that the immunity under the Speech and [sic] Debate Clause of the Constitution, particularly in view of the interpretation given that Clause by the Supreme Court in Johnson, shields Senator Brewster, constitutionally shields him from any prosecution for alleged bribery to perform a legislative act.
“I will, therefore, dismiss the odd counts of the indictment, 1, 3, 5, 7 and 9, as they apply to Senator Brewster.”
The United States filed a direct appeal to this Court, pursuant to 18 U. S. C. § 3731 (1964 ed., Supp. V).4 We postponed consideration of jurisdiction until hearing the case on the merits. 401 U. S. 935 (1971).
I
The United States asserts that this Court has jurisdiction under 18 U. S. C. § 3731 (1964 ed., Supp. V) to [505]*505review the District Court’s dismissal of the indictment against appellee. Specifically, the United States urges that the District Court decision was either “a decision or judgment setting aside, or dismissing [an] indictment. .. or any count thereof, where such decision or judgment is based upon the invalidity or construction of the statute upon which the indictment ... is founded” or a “decision or judgment sustaining a motion in bar, when the defendant has not been put in jeopardy.” If the District Court decision is correctly characterized by either of those descriptions, this Court has jurisdiction under the statute to hear the United States’ appeal.
In United States v. Knox, 396 U. S. 77 (1969), we considered a direct appeal by the United States from the dismissal of an indictment that charged the appellee in that case with violating 18 U. S. C. § 1001, a general criminal provision punishing fraudulent statements made to any federal agency. The appellee, Knox, had been accused of willfully understating the number of employees accepting wagers on his behalf when he filed a form that persons engaged in the business of accepting wagers were required by law to file. The District Court dismissed the counts charging violations of § 1001 on the ground that the appellee could not be prosecuted for failure to answer the wagering form correctly since his Fifth Amendment privilege against self-incrimination prevented prosecution for failure to file the form in any respect. We found jurisdiction under § 3731 to hear the appeal in Knox on the theory that the District Court had passed on the validity of the statute on which the indictment rested. 396 U. S., at 79 n. 2. The District Court in that case held that “§ 1001, as applied to this class of cases, is constitutionally invalid.” Ibid.
The counts of the indictment involved in the instant case were based on 18 U. S. C. § 201, a bribery statute. [506]*506Section 201 applies to "public officials,” and that term is defined explicitly to include Members of Congress as well as other employees and officers of the United States. Subsections (c)(1) and (g) prohibit the accepting of a bribe in return for being influenced in or performing an official act. The ruling of the District Court here was that “the Speech [or] Debate Clause of the Constitution, particularly in view of the interpretation given ... in Johnson, shields Senator Brewster . . . from any prosecution for alleged bribery to perform a legislative act.” Since § 201 applies only to bribery for the performance of official acts, the District Court’s ruling is that, as applied to Members of Congress, § 201 is constitutionally invalid.
Appellee argues that the action of the District Court was not “a decision or judgment setting aside, or dismissing” the indictment, but was instead a summary judgment on the merits. Appellee also argues that the District Court did not rule that § 201 could never be constitutionally applied to a Member of Congress, but that “based on the facts of this case” the statute could not be constitutionally applied. Under United States v. Sisson, 399 U. S. 267 (1970), an appeal does not lie from a decision that rests, not upon the sufficiency of the indictment alone, but upon extraneous facts. If an indictment is dismissed as a result of a stipulated fact or the showing of evidentiary facts outside the indictment, which facts would constitute a defense on the merits at trial, no appeal is available. See United States v. Findley, 439 F. 2d 970 (CA1 1971). Appellee claims that the District Court relied on factual matter other than facts alleged in the indictment.
An examination of the record, however, discloses that, with the exception of a letter in which the United States briefly outlined the theory of its ease against appellee, there were no “facts” on which the District Court could [507]*507act other than those recited in the indictment. Appellee contends that the statement “based on the facts of this case,” used by the District Judge in announcing his decision, shows reliance on the Government’s outline of its case. We read the District Judge’s reference to “facts,” in context, as a reference to the facts alleged in the indictment, and his ruling as holding that Members of Congress are totally immune from prosecution for accepting bribes for the performance of official, i. e., legislative, acts by virtue of the Speech or Debate Clause. Under that interpretation of § 201, it cannot be applied to a Member of Congress who accepts bribes that relate in any way to his office. We conclude, therefore, that the District Court was relying only on facts alleged in the indictment and that the dismissal of the indictment was based on a determination that the statute on which the indictment was drawn was invalid under the Speech or Debate Clause. As a consequence, this Court has jurisdiction to hear the appeal.
II
The immunities of the Speech or Debate Clause were not written into the Constitution simply for the personal or private benefit of Members of Congress, but to protect the integrity of the legislative process by insuring the independence of individual legislators. The genesis of the Clause at common law is well known. In his opinion for the Court in United States v. Johnson, 383 U. S. 169 (1966), Mr. Justice Harlan canvassed the history of the Clause and concluded that it
“was the culmination of a long struggle for parliamentary supremacy. Behind these simple phrases lies a history of conflict between the Commons and the Tudor and Stuart monarchs during which successive monarchs utilized the criminal and civil law to suppress and intimidate critical legisla[508]*508tors. Since the Glorious Revolution in Britain, and throughout United States history, the privilege has been recognized as an important protection of the independence and integrity of the legislature.” Id., at 178 (footnote omitted).
Although the Speech or Debate Clause’s historic roots are in English history, it must be interpreted in light of the American experience, and in the context of the American constitutional scheme of government rather than the English parliamentary system. We should bear in mind that the English system differs from ours in that their Parliament is the supreme authority, not a coordinate branch. Our speech or debate privilege was designed to preserve legislative independence, not supremacy.5 Our task, therefore, is to apply the Clause in such a way as to insure the independence of the legislature without altering the historic balance of the three co-equal branches of Government.
It does not undermine the validity of the Framers’ concern for the independence of the Legislative Branch to acknowledge that our history does not reflect a catalogue of abuses at the hands of the Executive that gave rise to the privilege in England. There is nothing in our history, for example, comparable to the imprisonment of a Member of Parliament in the Tower without a hearing and, owing to the subservience of some royal judges to the 17th and 18th century English kings, without meaningful recourse to a writ of habeas corpus:6 In fact, on only one previous occasion has this Court ever [509]*509interpreted the Speech or Debate Clause in the context of a criminal charge against a Member of Congress.
(a) In United States v. Johnson, supra, the Court reviewed the conviction of a former Representative on seven counts of violating the federal conflict-of-interest statute, 18 U. S. C. §281 (1964 ed.), and on one count of conspiracy to defraud the United States, 18 U. S. C. § 371. The Court of Appeals had set aside the conviction on the count for conspiracy to defraud as violating the Speech or Debate Clause. Mr. Justice Harlan, speaking for the Court, 383 U. S., at 183, cited the oft-quoted passage of Mr. Justice Lush in Ex parte Wason, L. R. 4 Q. B. 573 (1869):
“I am clearly of opinion that we ought not to allow it to be doubted for a moment that the motives or intentions of members of either House cannot be inquired into by criminal proceedings with respect to anything they may do or say in the House.” Id., at 577 (emphasis added).
In Kilbourn v. Thompson, 103 U. S. 168 (1881), the first case in which this Court interpreted the Speech or Debate Clause, the Court expressed a similar view of the ambit of the American privilege. There the Court said the Clause is to be read broadly to include anything “generally done in a session of the House by one of its members in relation to the business before it.” Id., at 204. This statement, too, was cited with approval in Johnson, 383 U. S., at 179. Our conclusion in Johnson was that the privilege protected Members from inquiry into legislative acts or the motivation for actual performance of legislative acts. Id., at 185.
In applying the Speech or Debate Clause, the Court focused on the specific facts of the Johnson prosecution. The conspiracy-to-defraud count alleged an agreement among Representative Johnson and three co-[510]*510defendants to obtain the dismissal of pending indictments against officials of savings and loan institutions. For these services, which included a speech made by Johnson on the House floor, the Government claimed Johnson was paid a bribe. At trial, the Government questioned Johnson extensively, relative to the conspiracy-to-defraud count, concerning the authorship of the speech, the factual basis for certain statements made in the speech, and his motives for giving the speech. The Court held that the use of evidence of a speech to support a count under a broad conspiracy statute was prohibited by the Speech or Debate Clause. The Government was, therefore, precluded from prosecuting the conspiracy count on retrial, insofar as it depended on inquiries into speeches made in the House.
It is important to note the very narrow scope of the Court’s holding in Johnson:
“We hold that a prosecution under a general criminal statute dependent on such inquiries [into the speech or its preparation] necessarily contravenes the Speech or Debate Clause. We emphasize that our holding is limited to prosecutions involving circumstances such as those presented in the case before us.” 383 U. S., at 184-185.
The opinion specifically left open the (question of a prosecution which, though possibly entailing some reference to legislative acts, is founded upon a “narrowly drawn” statute passed by Congress in the exercise of its power to regulate its Members’ conduct. Of more relevance to this case, the Court in Johnson emphasized that its decision did not affect a prosecution that, though founded on a criminal statute of general application, “does not draw in question the legislative acts of the defendant member of Congress or his motives for performing them.” Id., at 185. The Court did not [511]*511question the power of the United States to try Johnson on the conflict-of-interest counts, and it authorized a new trial on the conspiracy count, provided that all references to the making of the speech were eliminated.7
Three members of the Court would have affirmed Johnson's conviction. Mr. Chief Justice Warren, joined by Mr. Justice Douglas and Mr. Justice Brennan, concurring in part and dissenting in part, stated:
“After reading the record, it is my conclusion that the Court of Appeals erred in determining that the evidence concerning the speech infected the jury's judgment on the [conflict-of-interest] counts. The evidence amply supports the prosecution's theory and the jury’s verdict on these counts— that the respondent received over $20,000 for attempting to have the Justice Department dismiss an indictment against his [present] co-conspirators, without disclosing his role in the enterprise. This is the classic example of a violation of § 281 by a Member of the Congress. . . . The arguments of government counsel and the court’s instructions separating the conspiracy from the substantive counts seem unimpeachable. The speech was a minor part of the prosecution. There was nothing in it to inflame the jury and the respondent pointed with pride to it as evidence of his vigilance in protecting the financial institutions of his State. The record further reveals that the trial participants were well aware that a finding of criminality on one count did not authorize sim[512]*512ilar conclusions as to other counts, and I believe that this salutary principle was conscientiously followed. Therefore, I would affirm the convictions on the substantive counts.” Id., at 188-189. (Footnote omitted.)
Johnson thus stands as a unanimous holding that a Member of Congress may be prosecuted under a criminal statute provided that the Government’s case does not rely on legislative acts or the motivation for legislative acts. A legislative act has consistently been defined as an act generally done in Congress in relation to the business before it. In sum, the Speech or Debate Clause prohibits inquiry only into those things generally said or done in the House or the Senate in the performance of official duties and into the motivation for those acts.
It is well known, of course, that Members of the Congress engage in many activities other than the purely legislative activities protected by the Speech or Debate Clause. These include a wide range of legitimate “errands” performed for constituents, the making of appointments with Government agencies, assistance in securing Government contracts, preparing so-called "news letters” to constituents, news releases, and speeches delivered outside the Congress. The range of these related activities has grown over the years. They are performed in part because they have come to be expected by constituents, and because they are a means of developing continuing support for future elections. Although these are entirely legitimate activities, they are political in nature rather than legislative, in the sense that term has been used by the Court in prior cases. But it has never been seriously contended that these political matters, however appropriate, have the protection afforded by the Speech or Debate Clause. Careful examination of the decided cases reveals that the Court has regarded the protection as reaching only those things “generally done in a [513]*513session of the House by one of its members in relation to the business before it,” Kilbourn v. Thompson, supra, at 204, or things “said or done by him, as a representative, in the exercise of the functions of that office,” Coffin v. Coffin, 4 Mass. 1, 27 (1808).
(b) Appellee argues, however, that in Johnson we expressed a broader test for the coverage of the Speech or Debate Clause. It is urged that we held that the Clause protected from executive or judicial inquiry all conduct “related to the due functioning of the legislative process.” It is true that the quoted words appear in the Johnson opinion, but appellee takes them out of context; in context they reflect a quite different meaning from that now urged. Although the indictment against Johnson contained eight counts, only one count was challenged before this Court as in violation of the Speech or Debate Clause. The other seven counts concerned Johnson’s attempts to influence staff members of the Justice Department to dismiss pending prosecutions. In explaining why those counts were not before the Court, Mr. Justice Harlan wrote:
“No argument is made, nor do we think that it could be successfully contended, that the Speech or Debate Clause reaches conduct, such as was involved in the attempt to influence the Department of Justice, that is in no wise related to the due functioning of the legislative process. It is the application of this broad conspiracy statute to an improperly motivated speech that raises the constitutional problem with which we deal.” 383 U. S., at 172. (Emphasis added; footnote omitted.)
In stating that those things “in no wise related to the due functioning of the legislative process” were not covered by the privilege, the Court did not in any sense imply as a corollary that everything that “related” to the [514]*514office of a Member was shielded by the Clause. Quite the contrary, in Johnson we held, citing Kilbourn v. Thompson, supra, that only acts generally done in the course of the process of enacting legislation were protected.
Nor can we give Kilbourn a more expansive interpretation. In citing with approval, 103 U. S., at 203, the language of Chief Justice Parsons of the Supreme Judicial Court of Massachusetts in Coffin v. Coffin, 4 Mass. 1 (1808), the Kilbourn Court gave no thought to enlarging “legislative acts” to include illicit conduct outside the House. The Coffin language is:
“[The Massachusetts legislative privilege] ought not to be construed strictly, but liberally, that the full design of it may be answered. I will not confine it to delivering an opinion, uttering a speech, or haranguing in debate; but will extend it to the giving of a vote, to the making of a written report, and to every other act resulting from the nature, and in the execution, of the office: and I would define the article, as securing to every member exemption from prosecution, for every thing said or done by him, as a representative, in the exercise of the functions of that office without enquiring whether the exercise was regular according to the rules of the house, or irregular and against their rules. I do not confine the member to his place in the house; and I am satisfied that there are cases, in which he is entitled to this privilege, when not within the walls of the representatives’ chamber.” Id., at 27 (emphasis added).
It is suggested that in citing these words, which were also quoted with approval in Tenney v. Brandhove, 341 U. S. 367, 373-374 (1951), the Court was interpreting the sweep of the Speech or Debate Clause to be broader than Johnson seemed to indicate or than we today hold. Emphasis is placed on the statement that “there are [515]*515cases in which [a Member] is entitled to this privilege, when not within the walls of the representatives’ chamber.” But the context of Coffin v. Coffin indicates that in this passage Chief Justice Parsons was referring only to legislative acts, such as committee meetings, which take place outside the physical confines of the legislative chamber. In another passage, the meaning is clarified:
“If a member ... be out of the chamber, sitting in committee, executing the commission of the house, it appears to me that such member is within the reason of the article, and ought to be considered within the privilege. The body of which he is a member, is in session, and he, as a member of that body, is in fact discharging the duties of his office. He ought therefore to be protected from civil or criminal prosecutions for every thing said or done by him in the exercise of his functions, as a representative in committee, either in debating, in assenting to, or in draughting a report.” 8 4 Mass., at 28.
In no case has this Court ever treated the Clause as protecting all conduct relating to the legislative process.9 In every case thus far before this Court, the Speech or Debate Clause has been limited to an act which was [516]*516clearly a part of the legislative process — the due functioning of the process.10 Appellee’s contention for a broader interpretation of the privilege draws essentially on the flavor of the rhetoric and the sweep of the language used by courts, not on the precise words used in any prior case, and surely not on the sense of those cases, fairly read.
(c) We would not think it sound or wise, simply out of an abundance of caution to doubly insure legislative independence, to extend the privilege beyond its intended scope, its literal language, and its history, to include all things in any way related to the legislative process. Given such a sweeping reading, we have no doubt that there are few activities in which a legislator engages that he would be unable somehow to “relate” to the legislative process. Admittedly, the Speech or Debate Clause must be read broadly to effectuate its purpose of protecting the independence of the Legislative Branch, but no more than the statutes we apply, was its purpose to make Members of Congress super-citizens, immune from criminal responsibility. In its narrowest scope, the Clause is a very large, albeit essential, grant of privilege. It has enabled reckless men to slander and even destroy others with impunity, but that was the conscious choice of the Framers.11
[517]*517The history of the privilege is by no means free from grave abuses by legislators. In one instance, abuses reached such a level in England that Parliament was compelled to enact curative legislation.
“The practice of granting the privilege of freedom from arrest and molestation to members’ servants in time became a serious menace to individual liberty and to public order, and a form of protection by which offenders often tried — and they were often successful — to escape the penalties which their of-fences deserved and which the ordinary courts would not have hesitated to inflict. Indeed, the sale of 'protections’ at one time proved a source of income to unscrupulous members, and these parliamentary 'indulgences’ were on several occasions obtainable at a fixed market price.” C. Wittke, The History of English Parliamentary Privilege 39 (1921).
The authors of our Constitution were well aware of the history of both the need for the privilege and the abuses that could flow from too sweeping safeguards. In order to preserve other values, they wrote the privilege so that it tolerates and protects behavior on the part of Members not tolerated and protected when done by other citizens, but the shield does not extend beyond what is necessary to preserve the integrity of the legislative process. Moreover, unlike England with no formal, written constitutional limitations on the monarch, we defined limits on the co-ordinate branches, pro[518]*518viding other checks to protect against abuses of the kind experienced in that country.
It is also suggested that, even if we interpreted the Clause broadly so as to exempt from inquiry all matters having any relationship to the legislative process, misconduct of Members would not necessarily go unpunished because each House is empowered to discipline its Members. Article I, § 5, does indeed empower each House to “determine the Rules of its Proceedings, punish its Members for disorderly Behavior, and, with the Concurrence of two thirds, expel a Member,” but Congress is ill-equipped to investigate, try, and punish its Members for a wide range of behavior that is loosely and incidentally related to the legislative process. In this sense, the English analogy on which the dissents place much emphasis, and the reliance on Ex parte Wason, L. R. 4 Q. B. 573 (1869), are inapt. Parliament is itself “The High Court of Parliament” — the highest court in the land- — -and its judicial tradition better equips it for judicial tasks.
“It is by no means an exaggeration to say that [the judicial characteristics of Parliament] colored and influenced some of the great struggles over [legislative] privilege in and out of Parliament to the very close of the nineteenth century. It is not altogether certain whether they have been entirely forgotten even now. Nowhere has the theory that Parliament is a court — the highest court of the realm, often acting in a judicial capacity and in a judicial manner — persisted longer than in the history of privilege of Parliament.” Wittke, supra, at 14.
The very fact of the supremacy of Parliament as England’s highest tribunal explains the long tradition precluding trial for official misconduct of a member in any other and lesser tribunal.
In Australia and Canada, “where provision for legisla[519]*519tive free speech or debate exists but where the legislature may not claim a tradition as the highest court of the realm, courts have held that the privilege does not bar the criminal prosecution of legislators for bribery.” Note, The Bribed Congressman’s Immunity from Prosecution, 75 Yale L. J. 335, 338 (1965) (footnote omitted). Congress has shown little inclination to exert itself in this area.12 Moreover, if Congress did lay aside its normal activities and take on itself the responsibility to police and prosecute the myriad activities of its Members related to but not directly a part of the legislative function, the independence of individual Members might actually be impaired.
The process of disciplining a Member in the Congress is not without countervailing risks of abuse since it is not surrounded with the panoply of protective shields that are present in a criminal case. An accused Member is judged by no specifically articulated standards13 and is at the mercy of an almost unbridled discretion of the charging body that functions at once as accuser, prosecutor, judge, and jury from whose decision there is no established right of review. In short, a Member would be compelled to defend in what would be comparable to a criminal prosecution without the safeguards provided by the Constitution. Moreover, it would be somewhat naive to assume that the triers would be wholly objective and free from considerations [520]*520of party and politics and the passions of the moment.14 Strong arguments can be made that trials conducted in a Congress with an entrenched majority from one political party could result in far greater harassment than a conventional criminal trial with the wide range of procedural protections for the accused, including indictment by grand jury, trial by jury under strict standards of proof with fixed rules of evidence, and extensive appellate review.
Finally, the jurisdiction of Congress to punish its Members is not all-embracing. For instance, it is unclear to what extent Congress would have jurisdiction over a case such as this in which the alleged illegal activity occurred outside the chamber, while the appellee was a Member, but was undiscovered or not brought before a grand jury until after he left office:15
The sweeping claims of appellee would render Members of Congress virtually immune from a wide range of crimes simply because the acts in question were peripherally related to their holding office. Such claims are inconsistent with the reading this Court has given, not only to the Speech or Debate Clause, but also to the other legislative privileges embodied in Art. I, § 6. The very sentence in which the Speech or Debate Clause appears provides that Members “shall in all Cases, ex[521]*521cept Treason, Felony and Breach of the Peace, be privileged from Arrest during their Attendance at the Session of their Respective Houses. . . .” In Williamson v. United States, 207 U. S. 425 (1908), this Court rejected a claim, made by a Member convicted of subornation of perjury in proceedings for the purchase of public lands, that he could not be arrested, convicted, or imprisoned for any crime that was not treason, felony, or breach of the peace in the modern sense, i. e., disturbing the peace. Mr. Justice Edward Douglass White noted that when the Constitution was written the term "breach of the peace” did not mean, as it came to mean later, a misdemeanor such as disorderly conduct but had a different 18th century usage, since it derived from breaching the King’s peace and thus embraced the whole range of crimes at common law. Quoting Lord Mansfield, he noted, with respect to the claim of parliamentary privilege, “[t]he laws of this country allow no place or employment as a sanctuary for crime . . . .” Id., at 439.
The subsequent case of Long v. Ansell, 293 U. S. 76 (1934), held that a Member’s immunity from arrest in civil cases did not extend to civil process. Mr. Justice Brandéis wrote for the Court:
“Clause 1 [of Art. I, § 6] defines the extent of the immunity. Its language is exact and leaves no room for a construction which would extend the privilege beyond the terms of the grant.” Id., at 82.
We recognize that the privilege against arrest is not identical with the Speech or Debate privilege, but it is closely related in purpose and origin. It can hardly be thought that the Speech or Debate Clause totally protects what the sentence preceding it has plainly left open to prosecution, i. e., all criminal acts.
(d) Me. Justice White suggests that permitting the Executive to initiate the prosecution of a Member of Con[522]*522gress for the specific crime of bribery is subject to serious potential abuse that might endanger the independence of the legislature — for example, a campaign contribution might be twisted by a ruthless prosecutor into a bribery indictment. But, as we have just noted, the Executive is not alone in possessing power potentially subject to abuse; such possibilities are inherent in a system of government that delegates to each of the three branches separate and independent powers.16 In The Federalist [523]*523No. 73, Hamilton expressed concern over the possible hazards that confronted an Executive dependent on Congress for financial support.
“The Legislature, with a discretionary power over the salary and emoluments of the Chief Magistrate, could render him as obsequious to their will as they might think proper to make him. They might, in most cases, either reduce him by famine, or tempt him by largesses, to surrender at discretion his judgment to their inclinations.”
Yet Hamilton’s “parade of horribles” finds little real support in history. The check-and-balance mechanism, buttressed by unfettered debate in an open society with a free press, has not encouraged abuses of power or tolerated them long when they arose. This may be explained in part because the third branch has intervened with neutral authority. See, e. g., United States v. Lovett, 328 U. S. 303 (1946). The system of divided powers was expressly designed to check the abuses England experienced in the 16th to the 18th centuries.
Probably of more importance is the public reaction engendered by any attempt of one branch to dominate or harass another. Even traditional political attempts to establish dominance have met with little success owing to contrary popular sentiment. Attempts to “purge” uncooperative legislators, for example, have not been notably successful. We are not cited to any cases in which the bribery statutes, which have been applicable to Members of Congress for over 100 years,17 [524]*524have been abused by the Executive Branch. When a powerful Executive sought to make the Judicial Branch more responsive to the combined will of the Executive and Legislative Branches, it was the Congress itself that checked the effort to enlarge the Court. 2 M. Pusey, Charles Evans Hughes 749-765 (1951).
We would be closing our eyes to the realities of the American political system if we failed to acknowledge that many non-legislative activities are an established and accepted part of the role of a Member, and are indeed “related” to the legislative process. But if the Executive may prosecute a Member’s attempt, as in Johnson, to influence another branch of the Government in return for a bribe, its power to harass is not greatly enhanced if it can prosecute for a promise relating to a legislative act in return for a bribe. We therefore see no substantial increase in the power of the Executive and Judicial Branches over the Legislative Branch resulting from our holding today. If we underestimate the potential for harassment, the Congress, of course, is free to exempt its Members from the ambit of federal bribery laws, but it has deliberately allowed the instant statute to remain on the books for over a century.
We do not discount entirely the possibility that an abuse might occur, but this possibility, which we consider remote, must be balanced against the potential danger flowing from either the absence of a bribery statute applicable to Members of Congress or a holding that the statute violates the Constitution. As we noted at the outset, the purpose of the Speech or Debate Clause is to protect the individual legislator, not simply for his own sake, but to preserve the independence and thereby the integrity of the legislative process. But financial abuses by way of bribes, perhaps even more than Executive power, would gravely undermine legislative integrity and defeat the right of the [525]*525public to honest representation. Depriving the Executive of the power to investigate and prosecute and the Judiciary of the power to punish bribery of Members of Congress is unlikely to enhance legislative independence. Given the disinclination and limitations of each House to police these matters, it is understandable that both Houses deliberately delegated this function to the courts, as they did with the power to punish persons committing contempts of Congress. 2 U. S. C. § 194.
It is beyond doubt that the Speech or Debate Clause protects against inquiry into acts that occur in the regular course of the legislative process and into the motivation for those acts. So expressed, the privilege is broad enough to insure the historic independence of the Legislative Branch, essential to our separation of powers, but narrow enough to guard against the excesses of those who would corrupt the process by corrupting its Members. We turn next to determine whether the subject of this criminal inquiry is within the scope of the privilege.
Ill
An examination of the indictment brought against appellee and the statutes on which it is founded reveals that no inquiry into legislative acts or motivation for legislative acts is necessary for the Government to make out a prima facie case. Four of the five counts charge that appellee “corruptly asked, solicited, sought, accepted, received and agreed to receive” money “in return for being influenced ... in respect to his action, vote, and decision on postage rate legislation which might at any time be pending before him in his official capacity.” This is said to be a violation of 18 U. S. C. § 201 (c), which provides that a Member who “corruptly asks, demands, exacts, solicits, seeks, accepts, receives, or agrees to receive anything of value ... in [526]*526return for . . . (1) being influenced in his performance of any official act” is guilty of an offense.
The question is whether it is necessary to inquire into how appellee spoke, how he debated, how he voted, or anything he did in the chamber or in committee in order to make out a violation of this statute. The illegal conduct is taking or agreeing to take money for a promise to act in a certain way. There is no need for the Government to show that appellee fulfilled the alleged illegal bargain; acceptance of the bribe is the violation of the statute, not performance of the illegal promise.
Taking a bribe is, obviously, no part of the legislative process or function; it is not a legislative act. It is not, by any conceivable interpretation, an act performed as a part of or even incidental to the role of a legislator. It is not an “act resulting from the nature, and in the execution, of the office.” Nor is it a “thing said or done by him, as a representative, in the exercise of the functions of that office,” 4 Mass., at 27. Nor is inquiry into a legislative act or the motivation for a legislative act necessary to a prosecution under this statute or this indictment. When a bribe is taken, it does not matter whether the promise for which the bribe was given was for the performance of a legislative act as here or, as in Johnson, for use of a Congressman’s influence with the Executive Branch. And an inquiry into the purpose of a bribe “does not draw in question the legislative acts of the defendant member of Congress or his motives for performing them.” 383 U. S., at 185.
Nor does it matter if the Member defaults on his illegal bargain. To make a prima facie case under this indictment, the Government need not show any act of appellee subsequent to the corrupt promise for payment, for it is taking the bribe, not performance of the illicit compact, that is a criminal act. If, for example, there were undisputed evidence that a Member took a bribe in exchange [527]*527for an agreement to vote for a given bill and if there were also undisputed evidence that he, in fact, voted against the bill, can it be thought that this alters the nature of the bribery or removes it from the area of wrongdoing the Congress sought to make a crime?
Another count of the indictment against appellee alleges that he “asked, demanded, exacted, solicited, sought, accepted, received and agreed to receive” money “for and because of official acts performed by him in respect to his action, vote and decision on postage rate legislation which had been pending before him in his official capacity ...This count is founded on 18 U. S. C. §201 (g), which provides that a Member of Congress who “asks, demands, exacts, solicits, seeks, accepts, receives, or agrees to receive anything of value for himself for or because of any official act performed or to be performed by him” is guilty of an offense. Although the indictment alleges that the bribe was given for an act that was actually performed, it is, once again, unnecessary to inquire into the act or its motivation. To sustain a conviction it is necessary to show that appellee solicited, received, or agreed to receive, money with knowledge that the donor was paying him compensation for an official act. Inquiry into the legislative performance itself is not necessary; evidence of the Member’s knowledge of the alleged briber’s illicit reasons for paying the money is sufficient to carry the case to the jury.
Mb. Justice White rests heavily on the fact that the indictment charges the offense as being in part linked to Brewster’s “action, vote and decision on postage rate legislation.” This is true, of course, but our holding in Johnson precludes any showing of how he acted, voted, or decided. The dissenting position stands on the fragile proposition that it “would take the Government at its word” with respect to wanting to prove what we all agree [528]*528are protected acts that cannot be shown in evidence. Perhaps the Government would make a more appealing case if it could do so, but here, as in that case, evidence of acts protected by the Clause is inadmissible. The Government, as we have noted, need not prove any specific act, speech, debate, or decision to establish a violation of the statute under which appellee was indicted. To accept the arguments of the dissent would be to retreat from the Court’s position in Johnson that a Member may be convicted if no showing of legislative act is required.
Mr. Justice Brennan suggests that inquiry into the alleged bribe is inquiry into the motivation for a legislative act, and it is urged that this very inquiry was condemned as impermissible in Johnson. That argument misconstrues the concept of motivation for legislative acts. The Speech or Debate Clause does not prohibit inquiry into illegal conduct simply because it has some nexus to legislative functions. In Johnson, the Court held that, on remand, Johnson could be retried on the conspiracy-to-defraud count, so long as evidence concerning his speech on the House floor was not admitted. The Court’s opinion plainly implies that had the Government chosen to retry Johnson on that count, he could not have obtained immunity from prosecution by asserting that the matter being inquired into was related to the motivation for his House speech. See n. 7, supra.
The only reasonable reading of the Clause, consistent with its history and purpose, is that it does not prohibit inquiry into activities that are casually or incidentally related to legislative affairs but not a part of the legislative process itself. Under this indictment and these statutes no such proof is needed.
We hold that under these statutes and this indictment, prosecution of appellee is not prohibited by the Speech [529]*529or Debate Clause.18 Accordingly, the judgment of the District Court is reversed and the case is remanded for further proceedings consistent with this opinion.
Reversed and remanded.