The plaintiff Irving Stolberg brought an action in December 1969 in the United States District Court for the District of Connecticut under the Civil Rights Act, 42 U.S.C. § 1983, against the former president and members of the Board of Trustees of the Southern Connecticut State College (SCSC) based on their nonrenewal of his teaching contract and consequent denial of tenure, allegedly in violation of his First Amendment and Due Process rights. On February 29, 1972, Chief Judge M. Joseph Blumenfeld ordered entry of judgment for the plaintiff, directing that Stolberg be reinstated with tenure and no loss of seniority and further allowing $9,000 in compensatory damages to cover his loss of salary. The defendants did not seek review of that decision, but Stolberg appealed to this court asking for punitive damages, additional compensatory damages and attorney’s fees. This court’s opinion, reported at 474 F.2d 485 (1973), affirmed the denial of punitive damages and additional compensatory damages but reversed the denial of attorney’s fees and remanded for a determination of their amount.
After his dismissal, Stolberg became a successful candidate for the office of State Representative in 1970, and was sworn in as a member of the Connecticut General Assembly on January 6,1971. He was reelected in 1972 and 1974 and presently holds this office. After a delay of some two years, Stolberg resumed his professorship at SCSC on August 28, 1974. Having audited the payrolls submitted by the college, the State Auditors of Public Accounts sent letters to the Legislative Management Committee and to the then Governor, Hon. Thomas J. Meskill, on October 7, 1974 noting that under article 3, § 11 of the State Constitution1 no member of the General Assembly shall, during the term for which he is elected, hold any appointive position in the executive branch of the state government. In response to Governor Meskill’s inquiry, the Chairman of the Board of Trustees of SCSC advised him on October 17, 1974 that the Board was bound by the judgment of the United States District Court to return Stolberg to the faculty and that it was therefore inappropriate for the Trustees “to raise any questions with Mr. Stolberg concerning his position on the faculty.” The Comptroller had also raised the same issue with the Attorney General and on October 28,1974 the latter, relying upon his earlier opinion of February 9, 1971 which involved another state legislator who was teaching at a different State College, held that Stolberg was subject to the dual job ban, and further that under State ex rel. Butera v. Lombardi, 146 Conn. 299, 150 A.2d 309 (1959), when Stolberg became a member of the General Assembly he surrendered his position at SCSC and could not hold his position as an assistant professor at that institution.
On the basis of that opinion, the State Comptroller commenced withholding Stol*892berg’s bi-weekly SCSC checks commencing on November 6, 1974, and has continued to do so. The Board of Trustees has continued to submit Stolberg’s name to the State Comptroller for payment on each successive college payroll. On December 12, 1974, Stolberg filed an application and petition in the Connecticut. District Court for the issuance, of an order to show cause and for a contempt judgment naming as defendants the members .of the Board of Trustees of SCSC, and as respondents the Auditors of Public Accounts, the Governor, the Attorney General, the Assistant Attorney General, the Comptroller and certain subordinate state officials. The petition sought injunctive relief to enforce the prior judgment of the court, damages, basic salary, and counsel fees. Moreover, on June 11, 1975, after having filed almost 300 pages of briefs, plus exhibits and affidavits, plaintiff filed a motion for an interim order that he be paid his salary until the contempt motion was adjudicated. On June 23, 1975, Judge Blumenfeld denied the motion for a contempt judgment in an unpublished opinion in which, after reciting the facts, he stated:
The point of the judgment that the board offer to reinstate Stolberg was to put him in as good a position as he would have occupied but for the unconstitutional infringement of his first amendment rights. Although the judgment did not explicitly indicate that no decision on the merits of a dual-job ban claim had been made, I indicated to the parties in open court that I did not regard this issue as being in the case. . . .Now Stolberg seeks to use the judgment not as a shield against interference with his constitutional rights but as a sword predicated on grounds not litigated in the prior proceedings. This he may not do. The judgment is hereby clarified to indicate that it does not prejudice the state’s right to assert its constitutional dual-job ban against Stolberg. Any complaints Stolberg may have about the assertion of this ban must be raised in a separate proceeding (most appropriately brought in the state courts).
The motion for a contempt judgment is denied. (Footnote omitted). This appeal followed.
I
The appellant argues that the failure of the Board of Trustees defendants in the 1969 civil rights action to raise the dual job ban defense based on article 3, § 11 of the State Constitution and § 2-5 Conn.Gen. Stats.2 bars the present defendants from raising the issue as a ground for refusing to pay Stolberg’s salary at SCSC. The argument is posited on the principle that a final, valid determination on the merits is conclusive on the parties and those in privity with them, not only as to the matters adjudicated but those which could have been litigated in the prior action. Thus appellant invokes the doctrine of res judicata — the bar of the prior judgment extends “not only to all matters pleaded, but to all that might have been . . . .” Irving National Bank v. Law, 10 F.2d 721, 724 (2d Cir. 1926). Res judicata is thus distinguished from collateral estoppel where a prior judgment operates as an estoppel against a party only where there was an actual litigation and determination of the issue now in controversy, even though the subsequent action or claim is different. The distinction is ancient and well recognized. Lawlor v. National Screen Service Corp., 349 U.S. 322, 75 S.Ct. 865, 99 L.Ed. 1122 (1955); Commissioner of Internal Revenue v. Sunnen, 333 U.S. 591, 68 S.Ct. 715, 92 L.Ed. 898 (1948); Cromwell v. County of Sac, 94 U.S. 351, 24 L.Ed. 195 (1877); see IB J. Moore, Federal Practice ¶¶ 0.405[3], 0.441[1] (2d ed. 1974).
There is no basis for the application of the doctrine of collateral estoppel here. The issue of the dual job ban was never litigated in the 1969 civil rights action. In fact, no one claims that it was. The issue *893thus becomes whether or not under res judicata principles the present respondents are now barred by the fact that the dual job ban might have been raised by the defendants in that action but was not. The defendants’ pretrial memorandum in the initial action did raise the issue of the state constitutional and statutory ban on dual office holding. The pretrial report submitted by two special masters and endorsed “So Ordered” by a United States District Court Judge on May 7, 1971 indicated that Stolberg was then a member of the State Legislature and that the defendants would file an amended answer adding a special defense (presumably the dual job ban) within seven days. No such defense was ever interposed. However, at the close of trial, the plaintiff’s attorney, Louis M. Winer, called the attention of the court and the Assistant Attorney General, Sidney D. Giber, to the fact that the defendants had failed to file a defense “about the question of office holding while on the faculty.” The following colloquy ensued:
Court: So it’s not in the case. A dual job ban might affect the right to tenure?
Mr. Winer: It might affect his right to return. Well, I withdraw the comment.
Court: All right. Adjourn Court.
Thus the record not only reveals that the issue might have been litigated and that it was not, but that counsel for the plaintiff was perfectly well aware of it and did not press the point that it might affect his client’s right to return, and that the court, as its subsequent opinion makes clear, did not consider the issue to be in the case. Since it was not an issue in the case below and not argued on appeal our subsequent substantial affirmance of the judgment adds nothing to appellant’s position.
In view of Judge Blumenfeld’s understanding that the judgment below did not prejudice the Attorney General’s present position and the court’s subsequent clarification of its own judgment, it is difficult to understand how the general res judicata rubric, which precludes what “might” have been pleaded, can now be raised when the issue was deliberately eliminated from the case, with the apparent acquiescence of plaintiff’s counsel who, although recognizing that the issue might jeopardize his client’s return to the faculty, nonetheless withdrew his comment and did not press the point.
Res judicata makes a final order or judgment rendered in one proceeding conclusive under certain circumstances in another and different proceeding. Sunshine Coal Co. v. Adkins, 310 U.S. 381, 402, 60 S.Ct. 907, 84 L.Ed. 1263 (1940); United Shoe Mach. Co. v. United States, 258 U.S. 451, 458-59, 42 S.Ct. 363, 66 L.Ed. 708 (1922). Here, however, no second or different action has been brought. The relief sought by the petition below is essentially an enforcement of the judgment already entered in this case, joining as respondents state officials never parties to the initial action. The court which entered the judgment has unambiguously held that its terms did not preclude the Attorney General from subsequently relying upon the dual job ban. If the underlying judgment had explicitly provided that the dual job ban issue had not been litigated and that the defendants were not precluded from raising it, there would be no question that the injunctive relief and finding of contempt now sought would be properly denied. The court below has clarified its own judgment and the result should be no different.
That the issue was not in the case and was not deemed vital by either party or the court is perhaps understandable. It was not inevitable that Stolberg would continue to run for office and be elected nor was it inevitable that he would return to teaching at SCSC. His justifiable complaint was that he had been terminated for the exercise of free speech rights and not because he lacked ability to perform his job. His professional reputation was vindicated by the judgment which also awarded him $9,000 in compensatory damages and approximately $16,000 for counsel fees. While he was offered reinstatement and tenure at the close of the trial and judgment was entered directing reinstatement, he did not even seek to return to the college *894until August 28, 1974, more than two years after the judgment had been entered. He had in the interim found a teaching post at another college.
In addition to the uncertainty of Stolberg’s return to college and continuance in public office, the dual job ban of the Connecticut Constitution and statute presented unresolved questions of state law which, as Judge Blumenfeld has properly observed, are most appropriately determined by state courts. It is basic that a state court’s construction of its own constitution is definitive and binding upon the federal court. AF of L v. Watson, 327 U.S. 582, 596, 66 S.Ct. 761, 90 L.Ed. 873 (1946); Kelley v. Swenson, 481 F.2d 86, 89 (8th Cir. 1973); Sims v. Lane, 411 F.2d 661, 665-66 (7th Cir.), cert. denied, 396 U.S. 943, 90 S.Ct. 378, 24 L.Ed.2d 244 (1969). Moreover, there has been no state court decision construing the provision in the context here posed. Hence the reluctance of the federal district court to construe the state law is understandable. See Lehman Bros. v. Schein, 416 U.S. 386, 390, 94 S.Ct. 1741, 40 L.Ed.2d 215 (1974); Askew v. Hargrave, 401 U.S. 476, 478, 91 S.Ct. 856, 28 L.Ed.2d 196 (1971).
We note parenthetically that appellant has recognized the issue of comity, since on July 23, 1975, two days after filing his notice of appeal here, he commenced an action in the Superior Court of Connecticut seeking a declaratory judgment and other relief as to his right to compensation under the pertinent Connecticut constitutional and statutory provisions.
Appellant’s argument that his natural understanding was that since reinstatement had been ordered there would be no question of his right to salary is belied by his counsel’s letter to the Assistant Attorney General on June 26, 1973 which in pertinent part reads:
[Wjhat action will your office or the defendants take if Mr. Stolberg maintains his seat in the legislature and accepts reinstatement at Southern Connecticut? I am sure you recognize that there are. questions whether Article 3, Section 11 of the 1965 Constitution covers a teaching position at Southern Connecticut, and we wish to test this in a way that is least costly and risky for Mr. Stolberg. However, this would be no problem if the defendants and your office would take no action upon his return. Have you any precedent or earlier opinions, one way or the other, on the question whether Article 3, Section 11 covers someone teaching at a State College?
(Emphasis added). The letter is hardly consistent with the present posture of appellant that the prior judgment compelled salary payment despite the dual job ban and in fact indicates a full recognition that further litigation to test the applicability of the dual job ban to Stolberg would be necessary. In response, the Assistant Attorney General forwarded a copy of the prior adverse opinion of the Attorney General of February 9, 1971 with a covering letter which stated:
I am sure that you did not intend to ask that the Office of the Attorney General make any commitments, other than on behalf of the defendants. I am confident that you will render your client your usual sound legal advice on any questions he has raised.
The record and the exchange of correspondence to which we have referred demonstrate that not only the court but also counsel for both parties believed that the Attorney General was not prevented from raising the dual job ban when and if Stolberg returned to SCSC while still a member of the General Assembly. In fact, counsel for Stolberg indicated that the issue would have to be tested. Despite that recognition, the procedural tactic here adopted sought instead to circumvent any determination of the issue on the merits by recourse to a res judicata theory. In our view, the effort was properly thwarted below.
Appellant urges that the judgment rendered in the initial action is binding not only upon the president and Board of Trustees of SCSC but also upon those in privity with them. Hence, it is contended that the state officials named in the order to show cause, but not joined as defendants in the *895underlying action, should be held in contempt. This is a point we need not address since we have held that res judicata principles are not appropriately applied here. Judge Blumenfeld explicitly held that his judgment did not preclude the state from raising the dual job ban issue. As he indicated, that question is most appropriately litigated in the state courts where in fact it is now sub judice with a host of state officials, omitted as party defendants in the federal action now named as defendants therein.
For the reasons given the judgment below is affirmed.
. “No member of the general assembly shall, during the term for which he is elected, hold or accept any appointive position or office in the judicial or executive department of the state government, or in the courts of the political subdivisions of the state, or in the government of any county. . . .”
. “No member of the general assembly shall, during the term for which he is elected, be nominated, appointed or elected by the governor, the general assembly or any other appointing authority of this state to any position in the judicial, legislative or executive department of the state government, except as provided in this section. . . . ”