We affirm the judgment of the court of appeals.
Law of the Case
In Nolan v. Nolan (1984), 11 Ohio St.3d 1, 3-4,11 OBR 1, 2-3, 462 N.E.2d 410, 412-413, we summarized the doctrine of the law of the case:
“ * * * [T]he decision of a reviewing court in a case remains the law of that case on the legal questions involved for all subsequent proceedings in the case at both the trial and reviewing levels. * * *
“The doctrine is considered to be a rule of practice rather than a binding rule of substantive law and will not be applied so as to achieve unjust results. Gohman [v. St. Bernard (1924)], supra, 111 Ohio St. [726] at 730-731 [146 N.E. 291 at 292]. However, the rule is necessary to ensure consistency of results in a case, to avoid endless litigation by settling the issues, and to preserve the structure of superior and inferior courts as designed by the Ohio Constitution. See State, ex rel. Potain, v. Mathews (1979), 59 Ohio St.2d 29, 32 [13 O.O.3d 17, 18-19, 391 N.E.2d 343, 345].
“In pursuit of these goals, the doctrine functions to compel trial courts to follow the mandates of reviewing courts. * * * [Citations omitted.] Thus, where at a rehearing following remand a trial court is confronted with substantially the same facts and issues as were involved in the prior appeal, the court is bound to adhere to the appellate court’s determination of the applicable law. * * * [Citations omitted.] Moreover, the trial court is without authority to extend or vary the mandate given. * * * [Citations omitted.]” (Emphasis added.)
We have further held that the doctrine of law of the case precludes a litigant from attempting to rely on arguments at a retrial which were fully pursued, or *405available to be pursued, in a first appeal. New arguments are subject to issue preclusion, and are barred. Beifuss v. Westerville Bd. of Edn. (1988), 37 Ohio St.3d 187, 191, 525 N.E.2d 20, 24. See, also, Hawley v. Ritley (1988), 35 Ohio St.3d 157, 519 N.E.2d 390. Where this court refuses jurisdiction following the issuance of an opinion by a court of appeals, the court of appeals opinion becomes the law of the case. See Transamerica Ins. Co. v. Nolan (1995), 72 Ohio St.3d 320, 649 N.E.2d 1229.
On remand from the first decision of the court of appeals in Creed I, the appellees filed a cross-motion for summary judgment in their favor. The city officials did not contest appellant’s claim that she was entitled to judgment on the issue of the invalidity of Ordinance No. 29-89. They claimed that they were nevertheless entitled to judgment on the issues of damages and attorney fees, stating, “[t]he only issues remaining to be litigated are whether Mayor Sauline must repay the monies spent under Ordinance 29-89 and whether the plaintiff may recover attorney fees from either the City of Hubbard or the officers and councilmen who took part in the passing of the ordinance.” We find this acknowledgment to be in full accord with the doctrine of the law of the case.
In her first proposition of law, Creed’s administrator contends that Mayor Sauline’s state of mind as to the legality of the in-term pay raise ordinance at the time he accepted its benefits is irrelevant, thereby challenging the precedent of this court established in State ex rel. Parsons v. Ferguson (1976), 46 Ohio St.2d 389, 75 O.O.2d 457, 348 N.E.2d 692, and State ex rel. Gillie v. Warren (1973), 36 Ohio St.2d 89, 65 O.O.2d 241, 304 N.E.2d 242.
In opposition to this proposition the appellee city officials first argue that application of R.C. 731.07 to invalidate the pay-raise ordinance violates Section 3, Article XVIII of the Ohio Constitution, the Home Rule Amendment. We are precluded, however, from considering this argument, as to do so would violate the law-of-the-case doctrine. The finding of the court of appeals that R.C. 731.07 invalidated Ordinance No. 29-89 became the law of this case when this court refused to accept jurisdiction of the first appeal in 1992. We conclude that only two issues are properly before us: (1) whether Mayor Sauline should be required to reimburse amounts he had received as a result of Ordinance No. 29-89 through the end of his first term, and (2) whether relator Creed should have been awarded judgment in his favor on the issues of damages and attorney fees.
Reimbursement
In Parsons, swpra, and Gillie, supra, this court recognized that payments of compensation made to public officials, even if made erroneously or unconstitutionally, cannot ordinarily be recovered if made in good faith and under color of law. We today affirm this long-standing rule of law set forth in those cases and hold *406that a public official who accepts compensation contrary to statute is under no legal duty to repay the compensation where it is subsequently determined that the official received the compensation in good faith and under color of law.
Following remand, the trial court heard evidence to determine the factual issue whether the mayor’s receipt of increased salary benefits beginning in September 1989 and ending at the time of Creed I was “in good faith and under color of law,” and found that it was.
This court should not substitute its judgment for that of the trial court where the record contains competent and credible evidence supporting the findings of fact and conclusions of law rendered by a trial court judge. Gerijo, Inc. v. Fairfield (1994), 70 Ohio St.3d 223, 638 N.E.2d 533; Seasons Coal Co. v. Cleveland (1984), 10 Ohio St.3d 77, 80, 10 OBR 408, 411, 461 N.E.2d 1273, 1276; C.E. Morris Co. v. Foley Constr. Co. (1978), 54 Ohio St.2d 279, 8 O.O.3d 261, 376 N.E.2d 578. In the case at bar we find evidence in the record sufficient to support the trial court’s judgment.
The appellant’s evidence included the facts that from 1985 until at least 1987, while serving as a city councilman, Sauline had believed it to be illegal for the mayor to receive an in-term pay increase, and that Sauline nevertheless supported the city council’s decision to adopt Ordinance No. 29-89. Appellant further points to Ohio Ethics Commission Advisory Opinion No. 91-008, in which the commission has determined (1) that R.C. 102.03(D) prohibits a city mayor from approving the enactment of an ordinance which grants the mayor an increase in compensation, or from otherwise using his or her authority or influence, formally or informally, to secure an increase in compensation; and (2) that R.C. 102.03(E) prohibits a city mayor from accepting an in-term increase in compensation. We observe, however, that this opinion was issued in December 1991, after Mayor Sauline had received the greatest portion of the salary increase provided by Ordinance No. 29-89, and at the very end of the mayor’s first term. Quite obviously that advisory opinion could have had no effect on Mayor Sauline’s analysis of the legality of the pay raise ordinance before the opinion was rendered, and the record lacks any evidence as to when Mayor Sauline in fact first learned of its existence.
Sauline testified that, at the time the pay-increase ordinance was presented to him as mayor, the state of the law supported the conclusion that enactment of such a pay raise would be legal. He acknowledged that he had at times dining the past believed it illegal for an in-term mayor to receive a pay increase. His evidence tended to show, however, that he had discussed the legality of the proposed pay increase with the city of Hubbard law director on several occasions in 1989 prior to enactment of the ordinance, and that the law director advised him that such an in-term pay increase was legal. Other evidence showed that legal *407research performed by the law director prior to the enactment of the ordinance disclosed both a Trumbull County Common Pleas Court decision (State ex rel. Hamilton v. Madeline [Mar. 23, 1987], Trumbull C.P. No. 86-CV-1755, unreported) and an Ohio Attorney General Opinion (1983 Ohio Atty.Gen.Ops. No. 83-036, at 2-137) supporting the conclusion that the proposed pay raise would be legal. Moreover, the evidence showed that both Mayor Sauline and the law director spoke with examiners from the State Auditor’s office, and that the law director thereafter received a letter confirming that the auditor’s office no longer sought to recover funds received by non-charter city mayors resulting from in-term salary increases.
The record before this court contains sufficient evidence to support the trial court’s factual finding of good faith on the part of the appellees in implementing Ordinance No. 29-89, and we therefore affirm its judgment.
Attorney Fees
The trial court failed to award attorney fees to Creed’s administrator for the reason that “the court finds the Plaintiff is not entitled thereto” and because it found that the litigation resulted in “no benefit * * * to the residents and taxpayers of Hubbard, Ohio.”
As an additional reason for denying attorney fees, the court cited the plaintiffs failure to post security for the costs of the action as required by R.C. 733.59, although it is agreed the plaintiff had given $65 as a deposit for costs as required by Trumbull C.P.Loc.R. 17.01 upon the filing of any civil suit. The court inferred that the failure to deposit additional funds precluded a finding that the suit was indeed an R.C. Chapter 733 taxpayer suit, citing State ex rel. Citizens for a Better Portsmouth v. Sydnor (1991), 61 Ohio St.3d 49, 572 N.E.2d 649. We find, however, that pursuant to the law-of-the-case doctrine, the court exceeded its authority in making that determination. The clear import of Creed I was that Creed had indeed brought his action as an R.C. Chapter 733 taxpayer action. As such, the court was required to entertain appellant’s motion filed pursuant to R.C. 733.61, which provides:
“If the court hearing a case under section 733.59 of the Revised Code is satisfied that the taxpayer had good cause to believe that his allegations were well founded, or if they are sufficient in law, it shall make such order as the equity of the case demands. In such case the taxpayer shall be allowed his costs, and, if judgment is finally ordered in his favor, he may be allowed, as part of the costs, a reasonable compensation for his attorney.”
However, the trial court was not required to make an award of attorney fees. While R.C. 733.61 specifically provides that a successful plaintiff in a taxpayer suit shall be allowed his costs, it provides in contrast that an award of attorney *408fees may be allowed. Use of the word “may” in the statute implies that the decision to award attorney fees to a successful plaintiff in an R.C. Chapter 733 taxpayer suit lies entirely within the trial court’s discretion. State ex rel. Hirshler v. Frazier (1980), 63 Ohio St.2d 333, 335, 17 O.O.3d 418, 419, 410 N.E.2d 1253, 1254. Having reviewed the numerous reasons cited by the trial court in denying an award of attorney fees in this case, we do not find that the denial constituted an abuse of discretion. Cf. Kent v. Cent. Benefits Mut. Ins. Co. (1990), 67 Ohio App.3d 142, 586 N.E.2d 207.
For the foregoing reasons, the judgment of the court of appeals is affirmed.
Judgment affirmed.
Douglas, Wright, F.E. Sweeney, Pfeifer and Cook, JJ., concur. Resnick, J., dissents.