The opinion
PRESIDING JUSTICE CAHILL, dissenting:
I respectfully dissent. The material facts that control this case are undisputed. The law the majority construes in this case took effect May 30, 1995, to apply to collective bargaining agreements entered into after that date. On August 30, 1995, the Board sent Gordon a termination letter specifically referencing a 1993 contract and Article 42 of that contract as the grounds for termination. The 1995 contract, the only one to which Public Act 89 — 15 could apply, did not take effect until September 1, 1995, a day after Gordon was terminated.
Our supreme court has long adhered to the principle that courts of review will not issue advisory opinions merely to set precedent or guide future litigation. Segers v. Industrial Comm’n, 191 Ill. 2d 421, 428 (2000). Nor do we reach issues not essential to the disposition of the cause before us. Desnick v. Department of Professional Regulation, 171 Ill. 2d 510, 541 (1996). An advisory opinion results if the court resolves a question that is not presented by the facts of the case. People v. Murphy, 133 Ill. 2d 402, 408 (1990). Put another way, we have no power to declare a rule of law, which cannot affect the result of the case before us, to be a governing principle for future cases. Board of Trustees, Prairie State College v. Illinois Educational Labor Relations Board, 173 Ill. App. 3d 395, 413 (1988). Advisory opinions aside, a statute generally has no retroactive effect, and this is particularly true if it is employed to resolve a dispute based on a contract that predates the statute. First of America Bank v. Netsch, 166 Ill. 2d 165, 183 (1995).
. I do not necessarily disagree with the majority’s analysis of Public Act 89—15, but it cannot be used to resolve a dispute arising out of the 1993 contract, even if the parties are eager to know how they should behave in the future. The majority suggestion that none of the parties reused the issue and so waived it is less than persuasive. Principles of waiver apply to the parties, but not to the court. A.J. Maggio v. Willis, 316 Ill. App. 3d 1043 (2000).
For these reasons, I respectfully dissent.