The Arkansas Public Service Commission (Commission) and Southwestern Bell Telephone Company (Southwestern Bell) filed a joint motion with this court to dismiss the Attorney General’s appeal of Order No. 4 of the Arkansas Public Service Commission. In Order No. 4, the Commission held that it was in the public interest to allow Southwestern Bell to offer Caller-ID service in the Arkadelphia and West Memphis *48areas for a one-year trial period. The Commission also ordered Southwestern Bell to take affirmative action prior to the expiration of the trial period to either continue or discontinue the Caller-ID service. The Attorney General appealed from this order, contending the Commission’s establishment of a one-year trial period for Caller-ID service was not supported by substantial evidence. Subsequent to the filing of the Attorney General’s appeal, the Commission by an order in another docket approved permanent Caller-ID service, and the one-year trial period expired. As a result of these occurrences, the Commission and Southwestern Bell have moved to dismiss the Attorney General’s appeal of Order No. 4, contending’ that his appeal is now moot. We agree.
The only action the Commission took in Order No. 4 was to establish a one-year trial period for Caller-ID service. That trial period has now expired, and therefore, any rulings this Court might make in regard to Order No. 4 would have no effect. It is the duty of the court to decide actual controversies by a judgment which can be carried into effect and not give opinions upon abstract propositions or declare principles of law which cannot affect the matter in issue. Netherton v. Baldor Electric Co., 232 Ark. 940, 942, 341 S.W.2d 57 (1960). An issue is moot when it has no legal effect on an existing controversy; Killam v. Texas Oil and Gas Corp., 303 Ark. 547, 556-57, 798 S.W.2d 419 (1990); it is one in which a decision of the court on appeal could not afford the appellant any relief. Dotson v. Ritchie, 211 Ark. 789, 795, 202 S.W.2d 603 (1947).
We also note that, in earlier pleadings filed in this appeal, the Attorney General stated that his appeal would be moot at the end of the trial period. A party litigant is bound by his own pleadings and cannot maintain a position inconsistent therewith. International Harvester Co. v. Burks Motor, Inc., 252 Ark. 816, 821, 481 S.W.2d 351 (1972).
Accordingly, the joint motion of the Commission and Southwestern Bell is granted, and the appeal of the Attorney General is dismissed.