CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR THE SIXTH CIRCUIT.
Rehnquist, J., delivered the opinion of the Court, in which Burger, C. J., and Brennan, Marshall, Blackmun, Powell, Stevens, and O'connor, JJ., joined. White, J., filed an opinion concurring in the result, post, p. 174.
JUSTICE REHNQUIST delivered the opinion of the Court.
In March 1980, when the Environmental Protection Agency (EPA) tried to inspect one of respondent Stauffer Chemical Co.'s Tennessee plants using private contractors in addition to full-time EPA employees, Stauffer refused to allow the private contractors to enter the plant. Stauffer argues that private contractors are not "authorized representatives" as that term is used in § 114(a)(2) of the Clean Air Act, 84 Stat. 1687, 42 U. S. C. § 7414(a)(2) (1976 ed., Supp. V). Stauffer also argues that the Government should be estopped from relitigating the question of whether private contractors are "authorized representatives" under the statute because it has already litigated that question against Stauffer
and lost in connection with an attempted inspection of one of Stauffer's plants in Wyoming. The Court of Appeals agreed with Stauffer on the merits and also on the collateral-estoppel issue. Without reaching the merits, we affirm the Court of Appeals' holding that the Government is estopped from relitigating the statutory issue against Stauffer.
On March 27, 1980, officials from EPA and the State of Tennessee, accompanied by employees of a private firm under contract to EPA, attempted to inspect Stauffer's elemental phosphorus production plant in Mt. Pleasant, Tenn. Stauffer refused entry to the private contractors unless they would sign an agreement not to disclose trade secrets. When the private contractors refused to do so, the entire group left without making the inspection. EPA later obtained an administrative warrant authorizing the private employees to conduct the inspection, and Stauffer refused to honor the warrant.
On the following day, EPA began a civil contempt proceeding against Stauffer in Federal District Court in Tennessee, and Stauffer simultaneously moved to quash the warrant. It argued that private contractors are not "authorized representatives" under § 114(a)(2) of the Clean Air Act for the purposes of conducting inspections of premises subject to regulation under that Act.*fn1 The District Court denied Stauffer's motion to quash, accepting EPA's argument that the inspection authority conferred upon "authorized representatives" by the statute extends to private contractors retained by EPA. 511 F.Supp. 744 (MD Tenn. 1981).
On appeal, Stauffer reiterated its statutory argument and also asserted that the Government should be collaterally estopped on the basis of the decision in Stauffer Chemical Co. v. EPA, 647 F.2d 1075 (CA10 1981) (hereinafter Stauffer I), from contending that § 114(a)(2) authorizes private contractors to conduct inspections of Stauffer's plants. In Stauffer I officials of EPA and the State of Wyoming, accompanied by employees of a different private firm under contract to EPA, attempted to conduct an inspection of Stauffer's phosphate ore processing plant near Sage, Wyo. As in the present case, Stauffer insisted that the private contractors sign a nondisclosure agreement, and when they declined to do so, Stauffer refused to allow them to enter the plant. EPA obtained an administrative warrant authorizing the private contractors to conduct the inspection, and Stauffer refused to honor the warrant. Stauffer then instituted an action in United States District Court in Wyoming seeking to quash the warrant and to enjoin EPA from using private contractors in inspecting Stauffer's Wyoming plants. The District Court issued the injunction, and the United States Court of Appeals for the Tenth Circuit affirmed, holding that private contractors are not "authorized representatives" pursuant to § 114(a)(2). Id., at 1079.
The Sixth Circuit in the present case (hereinafter Stauffer II) reversed the District Court, adopting alternative grounds for its decision. Judge Weick, who delivered the opinion of the court, agreed with the Tenth Circuit that private contractors are not authorized to conduct inspections under the Clean Air Act. 684 F.2d 1174, 1181-1190 (1982). Relying on Montana v. United States, 440 U.S. 147 (1979), he also held that the Government was collaterally estopped by Stauffer I from litigating the statutory question again against Stauffer. 684 F.2d, at 1179-1181.*fn2 Judge Jones wrote a
separate opinion concurring on the collateral-estoppel issue and concluding that it was inappropriate for the court to reach the merits. Id., at 1190-1192. Judge Siler also wrote separately, dissenting from Judge Weick's opinion on the collateral-estoppel issue but concurring in his opinion on the merits. Id., at 1192-1193. For the reasons which follow, we agree that the doctrine of mutual defensive collateral estoppel is applicable against the Government to preclude relitigation of the same issue already litigated against the same party in another case involving virtually identical facts. Accordingly, we affirm the judgment of the Court of Appeals without reaching the merits.
In Montana v. United States, supra, we held that the United States was estopped from relitigating in federal court the question of whether the Montana gross receipts tax on contractors of public, but not private, construction firms violates the Supremacy Clause of the United States Constitution. A public contractor, financed and directed by the Federal Government, had already litigated that question in state court, and the Montana Supreme Court unanimously had upheld the tax. In approving the defensive use of collateral estoppel against the Government in Montana, we first determined that there was mutuality of parties, see United States v. Mendoza, ante, at 164, n. 9, that the issue sought to be relitigated was identical to the issue already unsuccessfully litigated in state court, and that there had been no change in controlling facts or legal principles since the state-court action. 440 U.S., at 155-162.
We next looked to see whether there were any special circumstances warranting an exception to the otherwise applicable rules of preclusion. One exception which we
mentioned as possibly relevant is the exception for "unmixed questions of law" arising in "successive actions involving unrelated subject matter." Id., at 162; see United States v. Moser, 266 U.S. 236, 242 (1924). Noting that the exception first articulated in Moser is "difficult to delineate," 440 U.S., at 163, we nonetheless had no trouble finding it inapplicable in Montana because of the close alignment in both time and subject matter between the federal-court and the state-court actions. Ibid.*fn3
Like Montana the case at bar involves the defensive use of collateral estoppel against the Government by a party to a prior action. The Government does not argue that the § 114(a)(2) issues in Stauffer I and Stauffer II are dissimilar nor that controlling law or facts have changed since Stauffer I. The Government instead argues that an exception to the normal rules of estoppel should apply because the statutory question here is an "unmixed question of law" arising in substantially unrelated actions. It also argues that the special role of the Government in litigating recurring issues of public importance warrants an exception in cases such as this one. We disagree with both of the Government's arguments.
As commonly explained, the doctrine of collateral estoppel can apply to preclude relitigation of both issues of law and
issues of fact if those issues were conclusively determined in a prior action. United States v. Mendoza, ante, p. 154; Allen v. McCurry, 449 U.S. 90, 94 (1980). Our cases, however, recognize an exception to the applicability of the principles of collateral estoppel for "unmixed questions of law" arising in "successive actions involving unrelated subject matter." Montana v. United States, supra, at 162; see also Allen v. McCurry, supra, at 95, n. 7; United States v. Moser, supra, at 242. While our discussion in Montana indicates that the exception is generally recognized, we are frank to admit uncertainty as to its application. The exception seems to require a determination as to whether an "issue of fact" or an "issue of law" is sought to be relitigated and then a determination as to whether the "issue of law" arises in a successive case that is so unrelated to the prior case that relitigation of the issue is warranted. Yet we agree that, for the purpose of determining when to apply an estoppel,
"[when] the claims in two separate actions between the same parties are the same or are closely related . . . it is not ordinarily necessary to characterize an issue as one of fact or of law for purposes of issue preclusion. . . . In such a case, it is unfair to the winning party and an unnecessary burden on the courts to allow repeated litigation of the same issue in what is essentially the same controversy, ...