delivered the opinion of the Court.
In
Hansberry
v.
Lee,
I
Jason Richards and Fannie Hill (petitioners) are privately employed in Jefferson County, Alabama. In 1991 they filed a complaint in the Federal District Court challenging the validity of the occupation tax imposed by Jefferson County *795 Ordinance 1120, which had been adopted in 1987. That action was dismissed as barred by the Tax Injunction Act, 28 U. S. C. § 1341. 1 They then commenced this action in the Circuit Court of Jefferson County.
Petitioners represent a class of all nonfederal employees subject to the county’s tax. 2 Petitioners alleged that the tax, which contains a lengthy list of exemptions, violates the Due Process and Equal Protection Clauses of the Fourteenth Amendment and similar provisions of the Alabama Constitution. Because $10 million of the annual proceeds from the county tax have been pledged to the Birmingham-Jefferson Civic Center for a period of 20 years, the court permitted the center to intervene and support Jefferson County’s defense of its tax.
The county moved for summary judgment on the ground that petitioners’ claims were barred by a prior adjudication of the tax in an earlier action brought by the acting director of finance for the city of Birmingham and the city itself. That earlier action had been consolidated for trial with a separate suit brought by three county taxpayers, and the Supreme Court of Alabama upheld the tax in the resulting appeal. See
Bedingfield
v.
Jefferson County,
On appeal, the county argued that the federal claims as well as the state claims were barred by the adjudication in
*796
Bedingfield.
The Alabama Supreme Court agreed. The majority opinion noted that in Alabama, as in most States, a prior judgment on the merits rendered by a court of competent jurisdiction precludes the relitigation of a claim if there is a “substantial identity of the parties” and if the “same cause of action” is presented in both suits.
The Alabama Supreme Court concluded that even though the opinion in
Bedingfield
did not mention any federal issue, the judgment in that case met these requirements. The court gave three reasons for this conclusion: (1) The complaints in the earlier case had alleged that the county tax violated the Equal Protection Clause of the Fourteenth Amendment and an equal protection issue had been argued in the appellate briefs,
Justice Maddox dissented. He agreed with the trial judge that no federal constitutional claim had been adjudicated in
Bedingfield.
*797 We now conclude that the State Supreme Court’s holding that petitioners are bound by the adjudication in Bedingfteld deprived them of the due process of law guaranteed by the Fourteenth Amendment. 3
II
State courts are generally free to develop their own rules for protecting against the relitigation of common issues or the piecemeal resolution of disputes.
Postal Telegraph Cable Co.
v.
Newport,
*798
The limits on a state court’s power to develop estoppel rules reflect the general consensus “ ‘in Anglo-American jurisprudence that one is not bound by a judgment
in perso-nam
in a litigation in which he is not designated as a party or to which he has not been made a party by service of process.’
Hansberry
v.
Lee,
Of course, these principles do not always require one to have been a party to a judgment in order to be bound by it. Most notably, there is an exception when it can be said that there is “privity” between a party to the second case and a party who is bound by an earlier judgment. For example, a judgment that is binding on a guardian or trustee may also bind the ward or the beneficiaries of a trust. Moreover, although there are clearly constitutional limits on the “privity” exception, the term “privity” is now used to describe various relationships between litigants that would not have come within the traditional definition of that term. See generally Restatement (Second) of Judgments, ch. 4 (1980) (Parties and Other Persons Affected by Judgments).
In addition, as we explained in Wilks:
“We have recognized an exception to the general rule when, in certain limited circumstances, a person, although not a party, has his interests adequately represented by someone with the same interests who is a party. See Hansberry v. Lee,311 U. S. 32 , 41-42 (1940) *799 (‘class’ or ‘representative’ suits); Fed. Rule Civ. Proc. 23 (same); Montana v. United States,440 U. S. 147 , 154-155 (1979) (control of litigation on behalf of one of the parties in the litigation). Additionally, where a special remedial scheme exists expressly foreclosing successive litigation by nonlitigants, as for example in bankruptcy or probate, legal proceedings may terminate pre-existing rights if the scheme is otherwise consistent with due process. See NLRB v. Bildisco & Bildisco,465 U. S. 513 , 529-530, n. 10 (1984) (‘[P]roof of claim must be presented to the Bankruptcy Court ... or be lost’); Tulsa Professional Collection Services, Inc. v. Pope,485 U. S. 478 (1988) (nonclaim statute terminating unsubmitted claims against the estate).”490 U. S., at 762, n. 2 .
Here, the Alabama Supreme Court concluded that res ju-dicata applied because petitioners were adequately represented in the
Bedingfield
action.
III
We begin by noting that the parties to the
Bedingfield
case failed to provide petitioners with any notice that a suit was pending which would conclusively resolve their legal rights. That failure is troubling because, as we explained in
Mullane
v.
Central Hanover Bank & Trust Co.,
Our answer is informed by our decision in
Hansberry
v.
Lee,
Despite the fact that the stipulation was untrue, the Illinois Supreme Court held that the second action was barred by res judicata. See
Lee
v.
Hansberry,
We recognized the “familiar doctrine . . . that members of a class not present as parties to the litigation may be bound by the judgment where they are in fact adequately repre
*801
sented by parties who are present, or . . . the relationship between the parties present and those who are absent is such as legally to entitle the former to stand in judgment for the latter.”
Hansberry,
Even assuming that our opinion in
Hansberry
may be read to leave open the possibility that in some class suits adequate representation might cure a lack of notice, but cf.,
id.,
at 40;
Eisen
v.
Carlisle & Jacquelin,
The Alabama Supreme Court concluded that the
“taxpayers
in the
Bedingfield
action adequately represented the interests of the taxpayers here,”
As a result, there is no reason to suppose that the
Beding-field
court took care to protect the interests of petitioners in the manner suggested in
Hansberry.
Nor is there any reason to suppose that the individual taxpayers in
Beding-field
understood their suit to be on behalf of absent county taxpayers. Thus, to contend that the plaintiffs in
Beding-field
somehow represented petitioners, let alone represented them in a constitutionally adequate manner, would be “to attribute to them a power that it cannot be said that they had assumed to exercise.”
Hansberry,
Because petitioners and the
Bedingfield
litigants are best described as mere “strangers” to one another,
Martin
v.
Wilks,
IV
Respondents contend that, even if petitioners did not receive the kind of opportunity to make their case in court that due process would ordinarily ensure, the character of their *803 action renders the usual constitutional protections inapplicable. They contend that invalidation of the occupation tax would have disastrous consequences on the county, which has made substantial commitments of tax revenues based on its understanding that Bedingfield determined the constitutionality of the tax. Respondents argue that in cases raising a public issue of this kind, the people may properly be regarded as the real party in interest and thus that petitioners received all the process they were due in the Bedingfield action.
Our answer requires us to distinguish between two types of actions brought by taxpayers. In one category are cases in which the taxpayer is using that status to entitle him to complain about an alleged misuse of public funds, see,
e. g., Massachusetts
v.
Mellon,
Because the guarantee of due process is not a mere form, however, there obviously exists another category of taxpayer cases in which the State may not deprive individual litigants of their own day in court. By virtue of presenting a federal constitutional challenge to a State’s attempt to levy personal funds, petitioners clearly bring an action of this latter type. Cf.
ibid,
(distinguishing between “public” and “private” actions). Indeed, we have previously struck down as a violation of due process a state court’s decision denying an individual taxpayer any practicable opportunity to contest a tax on federal constitutional grounds. See
Brinkerhoff-Faris Trust & Sav. Co.
v.
Hill,
*804 “We are not now concerned with the rights of the plaintiff on the merits, although it may be observed that the plaintiff’s claim is one arising under the Federal Constitution and, consequently, one on which the opinion of the state court is not final .... Our present concern is solely with the question whether the plaintiff has been accorded due process in the primary sense, — whether it has had an opportunity to present its case and be heard in its support. . . . [WJhile it is for the state courts to determine the adjective as well as the substantive law of the State, they must, in so doing, accord the parties due process of law. Whether acting through its judiciary or through its legislature, a State may not deprive a person of all existing remedies for the enforcement of a right, which the State has no power to destroy, unless there is, or was, afforded to him some real opportunity to protect it.” Id., at 681-682.
In any event, the Alabama Supreme Court did not hold here that petitioners’ suit was of a kind that, under state law, could be brought only on behalf of the public at large. Cf.
Corprew
v.
Tallapoosa County,
Of course, we are aware that governmental and private entities have substantial interests in the prompt and deter
*805
minative resolution of challenges to important legislation. We do not agree with the Alabama Supreme Court, however, that, given the amount of money at stake, respondents were entitled to rely on the assumption that the
Bedingfield
action “authoritatively established]” the constitutionality of the tax.
V
Because petitioners received neither notice of, nor sufficient representation in, the Bedingfield litigation, that adjudication, as a matter of federal due process, may not bind them and thus cannot bar them from challenging an allegedly unconstitutional deprivation of their property. Accordingly, the judgment of the Alabama Supreme Court is reversed, and the case is remanded to that court for further proceedings not inconsistent with this opinion.
It is so ordered.
Notes
Richards
v.
Jefferson County,
They were joined in the action by George Dykes and Joan Dykes, employees of the Federal Government who also work in the county. The Dykes represent a separate class of federal employees whose claims are not before us.
After granting the petition to consider both the equal protection challenge to the tax scheme, and the due process challenge to the Alabama Supreme Court’s conclusion that their claims were barred by the doctrine of res judicata, we entered an order dismissing the writ to the extent that it included the equal protection question and directing the parties to address at oral argument only the question whether the application of res judicata afforded petitioners due process.
“The doctrine of
res judicata
rests at bottom upon the ground that the party to be affected, or some other with whom he is in privity, has litigated or had an opportunity to litigate the same matter in a former action in a court of competent jurisdiction.
Southern Pacific R. R. Co.
v.
United States,
Of course, mere notice may not suffice to preserve one’s right to be heard in a case such as the one before us. The general rule is that “[t]he law does not impose upon any person absolutely entitled to a hearing the burden of voluntary intervention in a suit to which he is a stranger.”
Chase Nat. Bank
v.
Norwalk,
We need not decide here whether public officials are always constitutionally adequate representatives of all persons over whom they have jurisdiction when, as here, the underlying right is personal in nature. Cf.
Lockport
v.
Citizens for Community Action at Local Level, Inc.,
