Opinion for the Court filed by Circuit Judge STEPHEN F. WILLIAMS.
This case is the latest episode in a serial dispute between appellant John Stanton and the District of Columbia Court of Appeals (“DCCA”). Having been suspended from the bar under rules that did not automatically restore him on the lapse of his suspension, Stanton has thrice petitioned the DCCA for reinstatement. While the third petition was pending with that court, he filed suit in federal court posing constitutional challenges *74 both to the substantive provisions of the D.C. Rules of Professional Conduct (with which an applicant for reinstatement must be ready to comply in order to show fitness to practice), and to the procedures governing reinstatement.
The district court dismissed the claim on grounds of abstention under
Younger v. Harris,
:]: ;¡; *
On November 30, 1983 the DCCA issued two orders suspending Stanton from the practice of law. In both cases it found Stanton guilty of “neglect of a legal matter entrusted to him,” in violation of then-applicable Disciplinary Rule (“DR”) 6-101(A)(3), and “intentional failure to seek a client’s lawful objectives,” in violation of DR 7-101(A)(l). The DCCA ordered concurrent suspensions of a year and a day,
In re Stanton,
Since the original year-and-a-day suspension, Stanton has filed many actions in local and federal courts, all so far unavailing. In the present case, he asserts three claims. First, he argues that certain of D.C.’s Rules of Professional Conduct, successors of the rules he was originally found to have violated, deprive D.C. bar members of rights of free expression protected by the First Amendment. He specifically attacks Rule 1.2(a), insofar as it requires that in “a criminal case, the lawyer shall abide by the client’s decision, after consultation with the lawyer, as to a plea to be entered,” and Rule 1.3(a), which requires that a “lawyer shall *75 represent a client zealously and diligently within the bounds of the law.” As we shall see, these claims appear to be comprehensible — if at all — only in the context of Stanton’s personal quarrel with the DCCA over the lawyer’s role in the plea process.
In the procedural counts of his complaint, Stanton claims that the composition and procedures of the D.C. Board on Professional Responsibility violate the due process clause. (Stanton does not say, but he presumably means the due process clause of the Fifth Amendment, as it is that which applies to D.C.) On all three claims Stanton seeks declaratory relief.
* * *
Because it is jurisdictional, we first consider the
Rooker-Feldman
doctrine, set forth in
Rooker v. Fidelity Trust Co.,
In promulgating rather than applying bar rules, however, the DCCA acts in a legislative rather than a judicial capacity. Accordingly, a district court confronted with a simple challenge to the validity of such rules “is not reviewing a state-court judicial decision” and thus has subject matter jurisdiction.
Feldman,
How to detect the fatal “intertwining”? In
Feldman
itself plaintiffs attacked both a general rule of the DCCA and the refusal of that court to grant plaintiffs a waiver. The Court found the attack on the rule independent enough, noting that the rule did not even contemplate the waiver procedure that plaintiffs claimed had been applied unevenly.
Id.
at 487-88 & n. 18,
None of Stanton’s three claims lends itself to easy classification. The First Amendment count’s assertion that Rules 1.2(a) and 1.3(a) “restrict and curtail expression and practice of the dissident,” Complaint ¶ 22, seems to pose a general challenge. And Stanton’s request for a declaration that the rules are “in violation of the federal right to freedom of expression,”
id.
p. 6, bespeaks a claim independent of his personal situation. Cf.
Centifanti v. Nix,
Stanton’s articulation of his procedural theories is also multidirectional. On the one hand he notes that the DCCA has
processed
his reinstatement petitions under what he says are defective procedures, Complaint ¶ 6, and he devotes a good deal of energy to claiming that the
operations
of the Board, presumably as manifested in its proceedings on his many petitions, violate
D.C.
law (evidently believing, contrary to any number of cases,
2
that a state’s violation of its own procedures is ipso facto a violation of the federal Constitution), Complaint ¶¶ 10-14. But on the other hand much of his complaint is framed in very general terms, attacking the absence of notice to the public in the process of appointing Board members,
id.
¶ 9, and challenging what he characterizes as the unduly “limited review” powers of the DCCA over the Board,
id.
¶ 18. These contentions seem perfectly able to stand on their own feet, as would any facial challenge to agency rules brought under the relatively relaxed ripeness requirements of
Abbott Laboratories v. Gardner,
We now turn to the DCCA’s arguments that the judgments in those proceedings bar the current challenges, either on the ground that Stanton raised them and lost on the merits (issue preclusion), or on the ground that they were part of his earlier claims, so that he is barred for failure to raise them then (claim preclusion). At the outset Stanton objects that the DCCA did not plead res judicata before the trial court and hence cannot do so before us. Res judicata is an affirmative defense that may be lost if not pleaded in the answer; it may not ordinarily be asserted for the first time on appeal. See
Poulin v. Bowen,
This case, however, comes to us following the DCCA’s successful pre-answer motion to dismiss under Rules 12(b)(1) and 12(b)(6); no answer has yet been filed. Cf.
Harris v. U.S. Department of Veterans Affairs,
We can conceive of no reason for such judicial volleyball. Stanton, who argues the question of res judicata forcefully in his reply brief, Reply Br. at 6-9, suggests no way in which our resolution of the issue on appeal would prejudice him. And while res judicata exists in part to shield parties from duplicative and vexatious litigation, the interests that courts protect are also often their own— or, more precisely, those of society. “ ‘Courts today are having difficulty giving a litigant one day in court. To allow that litigant a second day is a luxury that cannot be afforded.’ ”
National Treasury Employees Union v. I.R.S.,
As res judicata belongs to courts as well as to litigants, even a
party’s
forfeiture of the right to assert it — which has not happened here because the defendant remains free to file an answer — does not destroy a
court’s
ability to consider the issue sua sponte. See
Nixon v. United States,
We give judgments of other courts the same preclusive effect as would the issuing court — in this case, the D.C. Court of Appeals. See 28 U.S.C. § 1738;
Matsushita Elec. Industrial Co. v. Epstein,
— U.S. -, -,
The DCCA has considered and rejected three of Stanton’s reinstatement petitions. See
Stanton III; Stanton TV; Stanton V.
In the first and third of these, Stanton raised constitutional arguments that the court refused to consider on res judicata grounds. See
Stanton III,
First, we note that because the D.C. courts have never considered Stanton’s due process claims on the merits, there is no possibility that issue preclusion would bar them. Issues may be deemed identical even though their factual contexts and underlying claims differ. See Restatement (Second) of Judgments § 27 comment c (1982) (factors *78 suggesting identity of issues include overlap between evidence and argument to be advanced, application of same rule of law, and relation between claims involved). Thus Stanton’s current attacks on the reinstatement procedures could involve the same issues as his earlier attacks on the suspension procedures. But the decisions in Stanton III and Stanton V rejected the challenges because of Stanton’s failure to raise them in the suspension proceedings, not because of any prior merits rejection — i.e., applying claim preclusion, not issue preclusion. Thus, assuming that there was sufficient identity in principle between Stanton’s due process attacks on D.C.’s suspension procedure and those on its reinstatement procedure for issue preclusion to be- even conceivable, the lack of merits consideration defeats any application of issue preclusion.
The general principle of claim preclusion is that a final, valid judgment on the merits precludes any further litigation between the same parties on the same cause of action.
3
Jurisdictions differ as to its reach largely because they start from different understandings of the scope of a “cause of action.” The District of Columbia, like the majority of jurisdictions, has adopted the Second Restatement’s “transactional” approach under which a “ ‘cause of action,’ for purposes of claim preclusion, comprises ‘all rights of the plaintiff to remedies against the defendant with respect to all or any part of the transaction, or series of connected transactions, out of which the action arose.’”
Smith v. Jenkins,
Admonitions to pragmatism do not decide cases, and this standard is obviously far from self-explanatory. Nor have the D.C. courts specifically articulated how they would treat a plaintiffs general prospective challenge to procedural rules that governed prior proceedings in which the plaintiff could have raised identical points. We thus look for guidance to broader principles of claim preclusion, and here the federal courts are instructive. 4
Federal law is clear that post-judgment
events
give rise to new claims, so that claim preclusion is no bar. Thus, if the plaintiff alleges a combination in restraint of trade, a new cause of action accrues each time it operates against him, and previous judgments do not bar repeated challenges.
Lawlor v. Nat’l Screen Service Corp.,
Similarly, each successive enforcement of a statute — such as each year a taxpayer is subjected to a tax — creates a new cause of action.
Commissioner v. Sunnen,
In civil litigation, too, parties may raise new issues in actions seeking to alter the playing field for future litigation, despite failure to raise them in past retrospective lawsuits. Thus in
Interoceanica Corp. v. Sound Pilots, Inc.,
Given these precedents, Stanton’s participation in prior proceedings in which facial challenges could have been raised does not prevent him from raising those challenges now, so long as they concern post-judgment events. And in fact they do: the procedures that he assails will govern future petitions for reinstatement. To put the conclusion into the standard “cause of action” language: Litigation of the validity of one past course of conduct is not the same “claim” as either (1) litigation over the validity of similar conduct occurring after the acts covered by the initial litigation (see
Lawlor,
We needn’t consider here whether claim preclusion ever permits two successive facial attacks on a statute. In characterizing the enactment of an ordinance as the “transaction” giving rise to a facial challenge, one court has concluded that at least the normal result would be a bar.
J.B.K., Inc. v. City of Kansas City,
We find that neither Rooker-Feldman nor claim preclusion bars Stanton’s due process claims. Accordingly, while we affirm the district court’s dismissal of the First Amend *80 ment claim, on Rooker-Feldman rather than Younger grounds, we reverse the judgment regarding Stanton’s procedural claims and remand the case for further proceedings consistent with this opinion.
So ordered.
Notes
. Current D.C. Bar Rule XI § 16(c) provides that reinstatement of attorneys suspended for more than one year prior to September 1, 1989 is governed by the requirements in effect at the time of the suspension. Accordingly, Stanton’s case is governed by Rule XI § 21 of the prior rules.
. See, e.g.,
Estelle v. McGuire,
. "Cause of action” and "claim” alternate throughout the caselaw. We use them interchangeably, following the cases discussed.
. The D.C. law of claim preclusion does not differ significantly from the federal. D.C. courts articulating the doctrine commonly cite federal cases applying federal law. See, e.g.,
Smith v. Jenkins,
