Chief Justice Burger
delivered the opinion of the Court.
The issue on appeal is whether a limitation of $250 on contributions to committees formed to support or oppose ballot measures violates the First Amendment.
I
The voters of Berkeley, Cal., adopted the Election Reform Act of 1974, Ord. No. 4700-N. S., by initiative. The campaign ordinance so enacted placed limits on expenditures and contributions in campaigns involving both candidates and ballot measures. Section 602 of the ordinance provides:
“No person shall make, and no campaign treasurer shall solicit or accept, any contribution which will cause the total amount contributed by such person with respect to a single election in support of or in opposition to a measure to exceed two hundred and fifty dollars ($250).”
Appellant Citizens Against Rent Control is an unincorporated association formed to oppose a ballot measure at issue in the April 19, 1977, election. The ballot measure would have imposed rent control on many of Berkeley’s rental units. To make its views on the ballot measure known, Citizens Against Rent Control raised more than $108,000 from approximately 1,300 contributors. It accepted nine contributions over the $250 limit. Those nine contributions totaled $20,850, or $18,600 more than if none of the contributions exceeded $250. Pursuant to § 604 of the ordinance, appellee Berkeley Fair Campaign Practices Commission, 20 days before the election, ordered appellant Citizens Against Rent Control to pay $18,600 into the city treasury.
Two weeks before the election, Citizens Against Rent Control sought and obtained a temporary restraining order prohibiting enforcement of §§ 602 and 604. The ballot measure relating to rent control was defeated. The Superior Court subsequently granted Citizens Against Rent Control’s motion for summary judgment, declaring that §602 was invalid on its face because it violated the First Amendment of the United States Constitution and Art. I, § 2, of the California Constitution. A panel of the California Court of Appeal unanimously affirmed that conclusion.
The California Supreme Court, dividing 4-3, reversed. 27 Cal. 3d 819, 614 P. 2d 742 (1980). Citing Buckley v. Valeo, 424 U. S. 1 (1976), the majority announced that it would strictly scrutinize § 602. It concluded that the section furthered compelling governmental interests because it ensured that special interest groups could not “corrupt” the initiative process by spending large amounts to support or oppose a ballot measure. Such corruption, the court found, could produce apathetic voters; these governmental interests were held to outweigh the First Amendment interests infringed upon. Finally, it concluded that § 602 accomplished its goal by the least restrictive means available. The California Supreme Court did not consider the disclosure requirements of the ordinance a sufficient prophylaxis to dispel perceptions of corruption.
We noted probable jurisdiction, 450 U. S. 908 (1981), and we reverse.
II
The appellees concede that the challenged ordinance has an impact on First Amendment rights; the parties disagree only as to the extent of the impact. Long ago this Court admonished that with respect to the First Amendment:
“[T]he power to regulate must be so exercised as not, in attaining a permissible end, unduly to infringe the protected freedom.” Cantwell v. Connecticut, 310 U. S. 296, 304 (1940).
This was but another way of saying that regulation of First Amendment rights is always subject to exacting judicial review.
We begin by recalling that the practice of persons sharing common views banding together to achieve a common end is deeply embedded in the American political process. The 18th-century Committees of Correspondence and the pamphleteers were early examples of this phenomena and the Federalist Papers were perhaps the most significant and lasting example. The tradition of volunteer committees for collective action has manifested itself in myriad community and public activities; in the political process it can focus on a candidate or on a ballot measure. Its value is that by collective effort individuals can make their views known, when, individually, their voices would be faint or lost.
The Court has long viewed the First Amendment as protecting a marketplace for the clash of different views and conflicting ideas. That concept has been stated and restated almost since the Constitution was drafted. The voters of the city of Berkeley adopted the challenged ordinance which places restrictions on that marketplace. It is irrelevant that the voters rather than a legislative body enacted § 602, because the voters may no more violate the Constitution by enacting a ballot measure than a legislative body may do so by enacting legislation.
Ill
A
The Court has acknowledged the importance of freedom of association in guaranteeing the right of people to make their voices heard on public issues:
“Effective advocacy of both public and private points of view, particularly controversial ones, is undeniably enhanced by group association, as this Court has more than once recognized by remarking upon the close nexus between the freedoms of speech and assembly.” NAACP v. Alabama, 357 U. S. 449, 460 (1958).
More recently the Court stated: “The First Amendment protects political association as well as political expression.” Buckley v. Valeo, supra, at 15.
Buckley also made clear that contributors cannot be protected from the possibility that others will make larger contributions:
“[T]he concept that government may restrict the speech of some elements of our society in order to enhance the relative voice of others is wholly foreign to the First Amendment, which was designed ‘to secure “the widest possible dissemination of information from diverse and antagonistic sources,”’ and ‘“to assure unfettered interchange of ideas for the bringing about of political and social changes desired by the people.”’ New York Times Co. v. Sullivan, [376 U. S.], at 266, 269, quoting Associated Press v. United States, 326 U. S. 1, 20 (1945), and Roth v. United States, 354 U. S., at 484. The First Amendment’s protection against governmental abridgment of free expression cannot properly be made to depend on a person’s financial ability to engage in public discussion. Cf. Eastern R. Conf. v. Noerr Motors, 365 U. S. 127, 139 (1961).” 424 U. S., at 48-49.
The Court went on to note that the freedom of association “is diluted if it does not include the right to pool money through contributions, for funds are often essential if ‘advocacy’ is to be truly or optimally ‘effective.’ ” Id., at 65-66. Under the Berkeley ordinance an affluent person can, acting alone, spend without limit to advocate individual views on a ballot measure. It is only when contributions are made in concert with one or more others in the exercise of the right of association that they are restricted by § 602.
There are, of course, some activities, legal if engaged in by one, yet illegal if performed in concert with others, but political expression is not one of them. To place a Spartan limit— or indeed any limit — on individuals wishing to band together to advance their views on a ballot measure, while placing none on individuals acting alone, is clearly a restraint on the right of association. Section 602 does not seek to mute the voice of one individual, and it cannot be allowed to hobble the collective expressions of a group.
Buckley identified a single narrow exception to the rule that limits on political activity were contrary to the First Amendment. The exception relates to the perception of undue influence of large contributors to a candidate:
“To the extent that large contributions are given to secure a political quid pro quo from current and potential office holders, the integrity of our system of representative democracy is undermined. . . .
“. . . Congress could legitimately conclude that the avoidance of the appearance of improper influence ‘is also critical... if confidence in the system of representative Government is not to be eroded to a disasterous extent.’ [CSC v. Letter Carriers,] 413 U. S., at 565.” 424 U. S., at 26-27.
Buckley thus sustained limits on contributions to candidates and their committees.
Federal Courts of Appeals have recognized that Buckley does not support limitations on contributions to committees formed to favor or oppose ballot measures. In C & C Plywood Corp. v. Hanson, 583 F. 2d 421 (1978), the Ninth Circuit struck down a Montana statute prohibiting corporate contributions supporting or opposing ballot measures. In so doing the court noted:
“The state interest in preventing corruption of officials, which provided the basis for the Supreme Court’s finding in Buckley that restrictions could permissibly be placed on contributions, is not at issue here.” Id., at 425.
Similarly, the Fifth Circuit interpreted Buckley to hold that
“[t]he sole governmental interest that the Supreme Court recognized as a justification for restricting contributions was the prevention of quid pro quo corruption between a contributor and a candidate.” Let’s Help Florida v. McCrary, 621 F. 2d 195, 199 (1980).
In First National Bank of Boston v. Bellotti, 435 U. S. 765 (1978), we held that a state could not prohibit corporations any more than it could preclude individuals from making contributions or expenditures advocating views on ballot measures. The Bellotti Court relied on Buckley to strike down state legislative limits on advocacy relating to ballot measures:
“Referenda are held on issues, not candidates for public office. The risk of corruption perceived in cases involving candidate elections [citations omitted] simply is not present in a popular vote on a public issue. To be sure, corporate advertising may influence the outcome of the vote; this would be its purpose. But the fact that advocacy may persuade the electorate is hardly a reason to suppress it: The Constitution ‘protects expression which is eloquent no less than that which is unconvincing.’ Kingsley Int’l Pictures Corp. v. Regents, 360 U. S., at 689.” 435 U. S., at 790 (footnote omitted).
Notwithstanding Buckley and Bellotti, the city of Berkeley argues that § 602 is necessary as a prophylactic measure to make known the identity of supporters and opponents of ballot measures. It is true that when individuals or corporations speak through committees, they often adopt seductive names that may tend to conceal the true identity of the source. Here, there is no risk that the Berkeley voters will be in doubt as to the identity of those whose money supports or opposes a given ballot measure since contributors must make their identities known under § 112 of the ordinance, which requires publication of lists of contributors in advance of the voting. See n. 4, supra.
Contributions by individuals to support concerted action by a committee advocating a position on a ballot measure is beyond question a very significant form of political expression. As we have noted, regulation of First Amendment rights is always subject to exacting judicial scrutiny. Supra, at 294. The public interest allegedly advanced by § 602 — identifying the sources of support for and opposition to ballot measures — is insubstantial because voters may identify those sources under the provisions of § 112. In addition, the record in this case does not support the California Supreme Court’s conclusion that §602 is needed to preserve voters’ confidence in the ballot measure process. Cf. Bellotti, supra, at 789-790. It is clear, therefore, that § 602 does not advance a legitimate governmental interest significant enough to justify its infringement of First Amendment rights.
B
Apart from the impermissible restraint on freedom of association, but virtually inseparable from it in this context, § 602 imposes a significant restraint on the freedom of expression of groups and those individuals who wish to express their views through committees. As we have noted, an individual may make expenditures without limit under § 602 on a ballot measure but may not contribute beyond the $250 limit when joining with others to advocate common views. The contribution limit thus automatically affects expenditures, and limits on expenditures operate as a direct restraint on freedom of expression of a group or committee desiring to engage in political dialogue concerning a ballot measure.
Whatever may be the state interest or degree of that interest in regulating and limiting contributions to or expenditures of a candidate or a candidate’s committees there is no significant state or public interest in curtailing debate and discussion of a ballot measure. Placing limits on contributions which in turn limit expenditures plainly impairs freedom of expression. The integrity of the political system will be adequately protected if contributors are identified in a public filing revealing the amounts contributed; if it is thought wise, legislation can outlaw anonymous contributions.
IV
A limit on contributions in this setting need not be analyzed exclusively in terms of the right of association or the right of expression. The two rights overlap and blend; to limit the right of association places an impermissible restraint on the right of expression. The restraint imposed by the Berkeley ordinance on rights of association and in turn on individual and collective rights of expression plainly contravenes both the right of association and the speech guarantees of the First Amendment. Accordingly, the judgment of the California Supreme Court is reversed, and the case is remanded for proceedings not inconsistent with this opinion.
Reversed and remanded.
Section 217 of the ordinance defines “measure” as “any City Charter amendment, ordinance or other propositions submitted to a popular vote at an election, whether by initiative, referendum or recall procedure or otherwise, or circulated for the purposes of submission to a popular vote at any election, whether or not the proposition qualifies for the ballot.”
It was not clear in 1977 whether § 602 would be enforced. The prohibition on contributions to ballot measure campaign committees by corporations and labor unions, § 605, was invalidated in Pacific Gas & Electric Co. v. City of Berkeley, 60 Cal. App. 3d 123, 131 Cal. Rptr. 350 (1976). Following Buckley v. Valeo, 424 U. S. 1 (1976), the city repealed a number of sections of the ordinance, such as § 513, which limited expenditures in support of or in opposition to a ballot measure to the lesser of $7,500 or 10 cents times the number of registered voters. When revising the ordinance to comply with these changes, the city mistakenly labeled § 602, the section challenged in this case, with the notation “do not enforce,” but it corrected this error approximately three months before the election involved in this case.
Section 604 states: “If any person is found guilty of violating the terms of this chapter, each campaign treasurer who received part or all of the contribution or contributions which constitute the violation shall pay promptly, from available campaign funds, if any, the amount received from such persons in excess of the amount permitted by this chapter to the City Auditor for deposit in the General fund of the City.”
To assure public awareness of the sources of support for committees, § 112 of the ordinance requires the publication of a list of all contributors of more than $50 in local newspapers twice during the last seven days of a campaign.
The value of the right to associate is illustrated by the cost of reaching the public. Appellants represent that the cost of a single mailing to each of the 71,088 persons registered to vote in Berkeley in 1977 was $12,800. App. 32. The cost of a full-page advertisement in a Berkeley area newspaper, the Independent Gazette, was $1,620. Note, 79 Mich. L. Rev. 1421, 1433, n. 54 (1981).
The dissent argues a case not before the Court. Its references to Bellotti relate to corporate contributions; § 602 limits contributions by “persons.” The dissent’s references to Buckley relate to contributions to candidates and their committees; the case before us relates to contributions to committees favoring or opposing ballot measures.