The primary issue in this case is whether the political activity clause of ORS 181.400(2) violates Article I, section 8, of the Oregon Constitution. It does. A secondary issue is whether plaintiffs are entitled to attorney fees as prevailing parties because they also pled a claim under 42 USC § 1983. They are not.
I.
ORS 181.400(2) provides in part:
“Notwithstanding any other law, no member of the state police shall in any way be active or participate in any political contest of any general or special election, except to cast the ballot of the member of the state police.”1
Plaintiffs are the Oregon State Police Officers Association (OSPOA), an employe organization representing all state police officers up to the rank of senior trooper, and Stephen Beck, OSPOA’s president. They sued the state, the Department of State Police, and the Department’s Superintendent (hereafter referred to collectively as “defendants”) for declaratory and injunctive relief. They contend that the political activity clause of ORS 181.400(2) violates Article I, section 8, of the Oregon Constitution, which provides:
“No law shall be passed restraining the free expression of opinion, or restricting the right to speak, write, or print freely on any subject whatever; but every person shall be responsible for the abuse of this right.”
They also contend that the clause violates Article I, section 20, of the Oregon Constitution (privileges or immunities clause), and the First and Fourteenth Amendments to the United States Constitution. See 42 USC § 1983.
After plaintiffs filed their complaint, but before trial, *534the Superintendent issued “guidelines” purporting to interpret ORS 181.400(2) and to clarify the political activity prohibited by that statute. The Superintendent issued the guidelines pursuant to ORS 181.280, which provides:
“The superintendent shall
‡ ‡ ‡ ‡
“(2) Make rules and regulations for the discipline and control of the state police.”2
The guidelines permit state police officers to campaign for or against nonpartisan candidates; to be candidates for and to hold nonpartisan offices (except trial judge, sheriff, and district attorney); to attend partisan candidates’ speeches and similar political meetings; to display bumper stickers on their personal vehicles and lawn signs at their personal residences; and to make monetary contributions to partisan and nonpartisan candidates. Officers may not be candidates for partisan office; participate in the management of a partisan political party or campaign; campaign for or against partisan candidates; solicit political contributions on behalf of partisan candidates, committees, or political parties; or participate actively in any effort organized by or on behalf of a partisan candidate or political party which is intended to solicit votes or contributions for or against a particular partisan candidate. The guidelines also permit broad political activity with regard to initiative and referendum petitions but require officers to give prior notice to the Superintendent before engaging in any ballot measure campaign activity.
Plaintiffs contend that the Superintendent’s guidelines violate the same state and federal constitutional provisions. They also contend that the guidelines deny them equal protection of the law because they are more restrictive of off-the-job political activity than ORS 260.432(2), Oregon’s *535“Little Hatch Act,” which applies to public employes generally.3 Plaintiffs are subject to the provisions of ORS 260.432(2). See ORS 260.432(4). Violation of ORS 260.432 is punishable by a civil penalty. ORS 260.995(1). Plaintiffs do not challenge the constitutionality of those restrictions, and the constitutionality of ORS 260.432(2) is not in issue here. Therefore, the question is whether the political restrictions placed on plaintiffs by the political activity clause of ORS 181.400(2) violate Article I, section 8, insofar as they are in excess of the restrictions imposed on plaintiffs by ORS 260.432(2).
The circuit court held that both the political activity clause of ORS 181.400(2) and the Superintendent’s guidelines are unconstitutionally overbroad under the state and federal constitutions and that they deny plaintiffs equal protection of the laws, and enjoined defendants from enforcing them. The court also awarded plaintiffs attorney fees on their 42 USC § 1983 claims.4
The Court of Appeals affirmed, holding that ORS 181.400(2) “is facially inconsistent with Article I, section 8,” and that no narrowing construction could save the statute. Oregon State Police Assn. v. State of Oregon, 94 Or App 478, 766 P2d 408 (1988). The Court of Appeals did not reach the other state or federal constitutional issues raised by the parties, but it affirmed the trial court’s award of attorney fees.5
*536II.
Plaintiffs do not argue that ORS 181.400(2) is unconstitutional as a direct prohibition on protected political speech. They argue only that the statute is overbroad. Defendants virtually concede that, standing alone, the statute is overbroad. They argue, however, that the narrowing interpretation of the Superintendent’s guidelines brings the political activity clause within constitutional bounds, and that the appropriate inquiry is whether the statute is constitutional as interpreted and implemented by the guidelines.
We first examine plaintiffs’ overbreadth claim under the Oregon Constitution. See Sterling v. Cupp, 290 Or 611, 614, 625 P2d 123 (1981). The state asserts that ORS 181.400(2) aims at maintaining a nonpolitical police force. Statutes directed at an effect of speech may be constitutional, unless the statute is overbroad. See, e.g., In re Lasswell, 296 Or 121, 673 P3d 855 (1983); State v. Robertson, 293 Or 402, 649 P2d 569 (1982); cf. Cooper v. Eugene Sch. Dist. No 4J, 301 Or 358, 723 P2d 298 (1986), appeal dismissed 480 US 942 (1987).
Political speech is an essential form of expression protected by Article I, section 8. See Ivancie v. Thornton, 250 Or 550, 553, 443 P2d 612 (1968), cert den 393 US 1018 (1969); Minielly v. State, 242 Or 490, 499, 411 P2d 69 (1966).6 In prohibiting any political activity or speech except voting, ORS 181.400(2) imposes restrictions that go far beyond any permissible limitation that the state may place on state police officers’ Article I, section 8, rights. The statute impermissibly prohibits state police officers from engaging in any manner in the political election process. Nothing in the record demonstrates that the promotion of the efficiency, integrity, and discipline of the state police requires the prohibition contained in ORS 181.400(2). See Minielly v. State, supra, 242 Or at 498-99. To paraphrase City of Hillsboro v. Purcell, 306 Or 547, 556, 761 P2d 510 (1988), the state may yet choose to *537regulate rather than totally proscribe the political activity of state police officers. The state has not yet done so.
III.
Ordinarily, an agency can inteipret a statute so as to exclude unconstitutional applications before the agency is forced to question the statute’s validity. Cooper v. Eugene Sch. Dist. No. 4J, supra, 301 Or at 365. Similarly, we will not construe a statute to violate constitutional prohibitions unless no other construction is possible. Roberts v. Mills, 290 Or 441, 447, 622 P2d 1094 (1981); State v. Smyth, 286 Or 293, 296, 593 P2d 1166 (1979). Here, no limiting regulation could be both consistent with the express prohibition of ORS 181.400(2) against any political activity except voting and at the same time narrow the statute’s scope within constitutional limits. ORS 181.400(2) cannot be saved by judicial or agency interpretation. We hold that the political activity clause of ORS 181.400(2) is overbroad in violation of Article I, section 8, of the Oregon Constitution.
Because we hold that the clause violates Article I, section 8, we need not determine plaintiffs’ claims under Article I, section 20, of the Oregon Constitution or under the First and Fourteenth Amendments. See Suess Builders v. City of Beaverton, 294 Or 254, 267, 656 P2d 306 (1982); Deras v. Myers, 272 Or 47, 53, 535 P2d 541 (1975).
IV.
We consider plaintiffs’ parallel federal claims only to the extent necessary to resolve defendants’ contention that the circuit court erred in awarding plaintiffs attorney fees under 42 USC § 1988.
We previously considered this issue in Roberts v. Mills, 291 Or 21, 628 P2d 714 (1981). In that case, Roberts sought his release from custody under both state habeas corpus law and 42 USC § 1983. He prevailed.7 When he later petitioned for attorney fees pursuant to 42 USC § 1988, this court denied his petition:
*538“A primary purpose of [42 USC] § 1983 is to provide a remedy for violation of a person’s civil rights where state remedies are inadequate. * * * Insofar as this case is concerned, the state remedy was procedurally and substantively adequate, and the federal enactment of § 1983 filled no void. The bare reference to § 1983 in the habeas corpus petition was proper, but it turned out to be superfluous. The invocation of § 1983 simply had no effect whatever upon the decision of the case or the relief granted.
U* * * * *
“The purpose of 42 USC § 1988 is to ensure that private citizens have a meaningful opportunity to vindicate the important congressional policies contained in the Civil Rights Act. Here, where an adequate state procedure exists for vindication of the juvenile’s right to be free from illegal restraint, we decline to award attorney fees under § 1988.” 291 Or at 24.8 (Citations and footnote omitted).
In Sterling v. Cupp, supra, 290 Or at 614, we explained that the state does not deny any right claimed under the federal Constitution when the claim before the court in fact is fully met by state law. See also Suess Builders v. City of Beaverton, supra, 294 Or 267; Deras v. Myers, supra, 272 Or at 53. In this case, state remedies are adequate to protect plaintiffs’ rights. Therefore, the state did not deny them any federal constitutional rights. Because plaintiffs were entitled to relief based upon an interpretation and application of the Oregon Constitution, their invocation of 42 USC § 1983 was unnecessary to the decision or the relief granted. We hold that the circuit court erred in awarding plaintiffs 42 USC § 1988 attorney fees.
There may be cases in which protection of a claimed right under Oregon statutory or constitutional law is in doubt, for instance, because lower court or responsible state agencies *539have previously rejected the claim, so that reliance on a federal constitutional guarantee reasonably can be said to be necessary. But this court’s modern decisions under Article I, section 8, should leave no basis to believe that a citizen of Oregon must invoke the federal constitution to protect rights to free political speech and participation.
The decision of the Court of Appeals is affirmed in part and reversed in part. The judgment of the circuit court holding that the political activity clause of ORS 181.400(2) violates Article I, section 8, of the Oregon Constitution, is affirmed. The judgment of the circuit court awarding plaintiffs attorney fees is reversed.
ORS 181.400 was enacted in 1931 and has remained substantially unchanged since that time. The statute has not been cited in or been the subject of any reported appellate decision. The statute itself does not contain a penalty clause. Nor is there any other statutory provision that specifically authorizes any criminal or civil penalty, forfeiture, sanction, or disciplinary action for a state police officer’s violation of ORS 181.400. The only apparent statutory sanction is found in ORS 181.290 (grounds for removal of state police).
The Superintendent asserts that the guidelines are an “internal management directive to establish personnel rules” and thus within a statutory exception to Administrative Procedures Act rulemaking requirements. See ORS 183.310(8)(a)(B). Plaintiffs do not challenge that assertion. Thus, we do not address whether the Superintendent does, in fact, have authority to promulgate guidelines without following Administrative Procedures Act rulemaking requirements, ORS 183.310 to 183.350. Nor do we decide whether, independent of ORS 181.400(2), the Superintendent has authority to impose greater restrictions on state police officers’ free speech rights than the legislature imposed on public employes generally in Oregon’s “Little Hatch Act,” ORS 260.432(2), infra, n 3.
ORS 260.432(2) provides:
“No public employe shall solicit any money, influence, service or other thing of value or otherwise promote any political committee or promote or oppose the nomination or election of a candidate, the adoption of a measure or the recall of a public office holder while on the job during working hours. However, this section does not restrict the right of a public employe to express personal political views.”
42 USC § 1988 provides:
“In any action or proceeding to enforce a provision of * * * [42 USC §] 1983 * * * the court, in its discretion, may allow the prevailing party * * * a reasonable attorney fee as part of the costs.”
The Court of Appeals relied on Lofft v. State Board of Higher Ed., 89 Or App 614, 750 P2d 515 (1988). No petition for review was filed in Lofft, and, therefore we had no occasion to review the Court of Appeals’ 42 USC § 1988 analysis in that case.
In Deras v. Myers, 272 Or 47, 62, 535 P2d 541 (1975), in holding that a statute limiting campaign expenditures violates Article I, section 8, of the Oregon Constitution, we stated:
“[The law] closes or impedes important channels of communication on public issues and thus denies citizens freedom of expression where the protection of that constitutional right is the most necessary to preserve our system of government.”
Roberts’ habeas corpus petition was based on both the state and federal constitutions. This court’s decision, Roberts v. Mills, 290 Or 441, 622 P2d 1094 (1981), does not indicate whether Roberts’ claim was sustained on state or federal constitutional grounds or both.
We recognize that nonavailability of attorney fees for state claims may cause plaintiffs to disfavor state claims when they have federal claims for which fees are available. Indeed, Justice Lent’s arguments in dissent in Roberts are not without merit. As Justice Brennan pointed out in Maine v. Thiboutot, 448 US 1, 11 n 12,100 S Ct 2502, 65 L Ed 2d 555 (1980), “if fees were not available in state courts, federalism concerns would be raised because most plaintiffs would have no choice but to bring their complaints concerning state actions to federal court.” However, after our decision in Roberts, 291 Or 21, those considerations are now in the hands of the legislature, which has not chosen to act in this area. See Friesen, Recovering Damages for State Bills of Rights Claims, 63 Tex L Rev 1269, 1303-10 (1985).