(dissenting).
This case illustrates the problems caused when courts disagree with an agency’s construction or interpretation of the statute it administers. Here the district court disagreed with the PERB’s interpretation of “impasse item” and, in view of our subsequent decision in West Des Moines Education Association v. PERB, 266 N.W.2d 118 (Iowa 1978), erred in doing so. Now this court rejects the PERB’s determination of the effect of a late arbitration decision. The situation is further complicated by this court’s decision just last month in City of Des Moines v. PERB, 275 N.W.2d 753 (Iowa 1979), again spurning a PERB construction of the statute, holding March 15 is a mandatory deadline for the bargaining process, subject to certain possible undisclosed exceptions.
Lurking in the shadows is the question of mootness. The present case involves bar*517gaining for a contract for the 1976-1977 school year. The time has passed. Presumably the schools were open, classes were taught, and teachers were compensated. Upon remand, arbitration is to be resumed to fix terms of a contract which, so far as the record discloses, cannot be performed.
The problems in this case point up the merit in the principle that courts should give weight to agency construction and interpretation of the statute it administers. See West Des Moines, 266 N.W.2d at 124-25. This is particularly true when agency procedures are implicated. We lack the specialized knowledge and breadth of data possessed by the agency, and frequently, as in this case, the agency is as good a judge of legislative policy as the courts are. We should not lightly substitute our notions of legislative intent for those of the agency. The predictability and regularity of the administrative process is at stake. The more we interfere with an agency’s decisions, the more we disrupt its processes and our own. Agency decisions lack finality, and litigation is fostered. Increased costs, delay and uncertainty result. Moreover, courts simply do not have the capacity to make agency decisions in addition to judicial decisions.
I. Mootness. The present controversy concerns events which occurred subsequent to the mandatory March 15 cut-off date for collective bargaining delineated in City of Des Moines. This fact would moot the controversy except for the court’s holding today that the deadline is non-jurisdictional and has been waived. It is difficult to see how this holding serves the cause of effective and orderly delivery of government services espoused in City of Des Moines.
However, the case appears to be moot for a different reason. This is not a case involving enforcement of rights, like a claim for back pay, under a past contract; it concerns establishment of a contract for personal services which, by reason of passage of time, cannot be performed under the contract so established. The court’s holding ostensibly affect events which are beyond recall. If so, the case is moot. Local No. 8-6, Oil, Chemical & Atomic Workers International Union v. Missouri, 361 U.S. 363, 80 S.Ct. 391, 4 L.Ed.2d 373 (1960); CWA v. Southern Bell Telephone and Telegraph Company, 419 F.2d 1310 (5 Cir. 1970); Interstate Bakeries Corp. v. Bakery, Cracker, Pie and Yeast Wagon Drivers Union, Local 734, 58 Ill.App.2d 485, 208 N.E.2d 397 (1965).
If the controversy is moot, the question should not be decided unless the criteria delineated in Board of Directors of Independent School District of Waterloo v. Green, 259 Iowa 1260, 147 N.W.2d 854 (1967), are met. I do not believe the public interest exception applies here.
The problem in division I is addressed in Salsbury Laboratories v. Iowa Department of Environmental Quality, 276 N.W.2d 830 (Iowa 1979), and the question in division II was answered in the West Des Moines case.
The holding in division III rests upon speculation about potential for arbitration deadlock in a case where the arbitration process was complicated by use of a wide-open definition of impasse item instead of the narrow definition subsequently adopted by this court in West Des Moines.
The West Des Moines decision was predicated on reasoning that the legislature intended to narrow the differences of the parties to require hard bargaining before the arbitration stage. We believed offers on subject category impasse items would be more likely to be reasonable because of the desirability of having the factfinder as an ally in entering arbitration. If this belief is justified, the prospect of a deadlock during arbitration is minimized.
Prudence dictates the desirability of waiting until the issue is presented in a case where the West Des Moines holding has been applied. We would then have a better perspective on the problem.
It is also significant that the issue is here decided based upon a perception about potential for deadlock in a case where deadlock did not occur even though the wide-open concept of impasse item was used. The record contains no data showing deadlock has ever occurred in arbitration, nor *518does it contain any information upon which the costs in time and money of the procedures adopted by the court today can be calculated.
The issue does not have to be decided in this case, and I do not believe it should be. I would ask the parties to show cause why the appeal should not be dismissed for mootness.
II. Effect of noncompliance with the arbitration time limit On the merits, I do not believe the holding in division III has any basis under established principles of statutory interpretation.
In City of Des Moines the court said, “Whether the individual times set in §§ 20.20- 22 are directory or mandatory has no bearing on the result in this case.” 275 N.W.2d at 761. It follows that the result in that case does not control our determination whether an arbitration decision is invalid unless made within fifteen days of the first meeting of the arbitrators.
Similarly, neither International Association of Firefighters v. City of Johnstown, 468 Pa. 96, 360 A.2d 197 (1976), or Town of Tiverton v. Fraternal Order of Police, 372 A.2d 1273 (R.I.1977), is authority for the court’s holding. Those cases involved the same problem as City of Des Moines, and, unlike Iowa, each jurisdiction had a statute requiring arbitration requests to be made a fixed number of days before a budgetary deadline. An arbitration timetable is distinguished from such a provision in Town of Tiverton. See 372 A.2d 1275. It is also noteworthy that in City of Johnstown, despite holding the time limitation for requesting arbitration to be mandatory, the court held that dilatory conduct by the public employer excused the employee group from meeting the schedule.
Certainly it is not necessary to the purpose of the PER Act to hold that the time provisions of the schedule for impasse steps are mandatory. The budget-filing deadlines do not require it. If every statutory impasse step were pursued on schedule, the process would be completed within sixty-seven days. See §§ 20.21, .22(1), .22(2), .22(5) and .22(11). When the parties agree on impasse procedures, section 20.17 gives them until one hundred twenty days before the certified budget submission date of the public employer to commence them. The legislature built substantial leeway into the schedule for impasse procedures.
This is entirely reasonable. People do not function like machines. Employee groups and employers vary greatly in size and location in this state. Their resources, needs and problems differ. They do not have identical capacities to respond to the statutory schedule. Their ability to do so may be affected by many fortuitous events, not the least of which are weather, illness and other manifestations of human frailty. In view of these realities, I do not believe the legislature imposed deadlines upon them which are intended to have punitive effects. I believe the legislature provided the time frame for impasse procedures from a desire to secure system, uniformity and dispatch in the public business, not to invalidate late agreements even when no prejudice is shown.
The court’s decision assumes the ten-day deadline for mediation and the fifteen-day deadline for factfinding in section 20.21 are directory rather than mandatory. We have no basis in the statute for holding that the legislature meant something different when it also used the word “shall” in the succeeding subsection in imposing the fifteen-day deadline on arbitration. See § 20.22(11). Under our holding in Taylor v. Department of Transportation, 260 N.W.2d 521, 522-524 (Iowa 1977), these provisions are plainly directory rather than mandatory. They impose a duty to keep the schedule, but a failure to do so will not invalidate subsequent proceedings unless prejudice is shown.
In addition to the standard delineated in Taylor, this conclusion is supported by other principles of statutory construction.
The fifteen-day arbitration deadline in section 20.22(11) is couched in affirmative language. Nothing in the provision expressly invalidates a late decision or inferentially makes timeliness a condition prece*519dent. These factors are characteristics of directory statutes. Upon this reasoning a similar arbitration deadline was held to be directory in International Brotherhood of Teamsters Local 145 v. Shapiro, 138 Conn. 57, 82 A.2d 345 (1951).
It is also significant that the parties have no control of the action of the arbitrators. This has been recognized as an additional factor which supports holding that a statute fixing a time limit for an arbitration decision is directory. Ordinarily a litigant should not be denied the fruits of litigation because the judge fails to decide a case by a particular day. The same principle applies to arbitration. Pingree v. State Court of Mediation and Arbitration, 130 Mich. 229, 89 N.W. 943 (1902).
Such a holding is also consistent with our duty to construe the PER Act liberally with a view toward promoting its objects and assisting the parties in obtaining justice. See § 4.2, The Code. Impasse procedures are complex enough without introducing the complication of mandatory deadlines into them.
Additional cases holding arbitration decision deadlines to be directory include West Rock Lodge No. 2120, International Association of Machinists v. Geometric Tool Co., 406 F.2d 284 (2 Cir. 1968), and City of Spokane v. Spokane Police Guild, 87 Wash.2d 457, 553 P.2d 1316 (1976).
It is also significant that in amending section 20.17 to fix a March 15 deadline for state-level collective bargaining agreements, the legislature did not treat the timetable for statutory impasse procedures as mandatory. Instead, the amendment directed the PERB to provide, by rule, “a date on which any impasse item must be submitted to binding arbitration and for such other procedures as deemed necessary to provide for the completion of negotiations of proposed state collective bargaining agreements not later than March fifteenth.” The amendment did not stop there. The legislature did not rely upon the fifteen-day period for reaching an arbitration decision in section 20.22(11). The amendment added this requirement: “The date selected for the mandatory submission of impasse items to binding arbitration shall be sufficiently in advance of March fifteenth to insure that the arbitrators’ decision can be reasonably made before March fifteenth.” See 1977 Extra Session, 67 G.A., ch. 1, § 26. This part of the amendment would not be necessary if the legislature intended the fifteen-day period in section 20.22(11) to be mandatory.
III. Policy considerations. I do not believe speculation about potential for deadlock in the arbitration process can justify holding that the fifteen-day limitation in section 20.22(11) is mandatory. No empirical data supports that speculation. It assumes arbitrators selected by the parties will lockstep with the parties’ offers and the “neutral” arbitrator will lockstep with the factfinder. This assumption is unwarranted. It is wholly contrary to the principle which underlies any system of arbitration. The task of arbitrators is to reach a decision, just as other adjudicators, including courts, do. Labor arbitrators are not automatons who inflexibly adhere to a one-dimensional view. Ordinarily, they are well-paid, highly-trained and skilled experts in the art of compromise. I believe arbitrators can be trusted to reach decisions even though they are not judges.
Furthermore, giving an arbitration panel a maximum fifteen-day life will remove one important inducement for the arbitrators to make a decision. They are more likely to reach agreement if they know the buck stops with them than if they know they will be replaced by another panel if they do not agree within fifteen days.
Of equal importance, it is unlikely that the goal of avoiding delay caused by deadlock will be achieved by aborting arbitration and starting it anew if an arbitration decision is not made in the relatively short span of fifteen days. The statute allows seventeen days for the mechanics of selecting and convening the panel of arbitrators. Additional time is taken in submitting the dispute. All of this time, in addition to the fifteen days exhausted by the deliberations of the panel, will be wasted when the par*520ties are required to start anew. If successive panels fail to issue a decision within fifteen days, the wasted time, effort and expense will become proportionately greater.
If arbitrators cannot be relied upon to reach a decision within a reasonable time, how do we know that a second or third panel will be more likely to do so than the first one?
IV. Responding to the public interest. It is incongruous to hold that the arbitration deadline in § 20.22(11) is mandatory because the public interest demands it and at the same time hold that the parties, including the employee bargaining unit, may nevertheless waive it by agreement or by failing to object to delay. If the deadline is essential to the purpose of the Act, it should not be subject to waiver by the parties. They should not have the right to subvert the policy of the statute. The District’s position is consistent. It insists that all the deadlines in the statute are both mandatory and jurisdictional.
Despite the court’s effort to ameliorate the harshness of its holding by saying that the deadline in section 20.22(11) is not jurisdictional, I am afraid the court has put a premium on delay by its decision in City of Des Moines v. PERB, which will lead to cases in which delay in collective bargaining becomes a tactic to defeat an agreement. In those situations we can expect that the courts will be asked to find deadlines to be unenforceable because of' waiver or upon some other theory. See International Association of Firefighters v. City of Johnstown; Wingert v. Urban, 250 N.W.2d 731 (Iowa 1977).
We do not foster public employer-employee harmony by adopting procedures which have the potential of putting every case in which a deadline is not met into litigation so the courts may decide, on an ad hoc basis, which delays were permissible and which were not. Consequently the procedures cannot fairly be said to respond to the public’s interest in labor peace.
V. Lack of basis in the statute. Finally, the procedures adopted by this court for substituting a new panel of arbitrators are not provided in the statute being interpreted, and they do not merely fill statutory interstices. They rest on considerations of policy which are within the legislative prerogative.
The only provision in the statute for convening a arbitration panel is in section 20.-22. The only panel for which the parties submit names is the one called," the panel of arbitrators” sixteen times in this provision. Nowhere is there a reference to “a panel of arbitrators”. The time frame for selection of the panel starts four days after a party’s initial request for binding arbitration. This request is the only basis for triggering the naming of a panel. A provision is made for filing a vacancy, but the only schedule provided is tailored to choosing a single panel. No provision is made for selection or deliberations of a second panel.
In these circumstances I cannot believe the legislature intended that the panel of arbitrators would be discharged and a new panel selected if an arbitration decision is not made within fifteen days. Even if the result were desirable, it is not our function to modify the statute.
Assuming the merits of this case should be decided, I would hold that the fifteen-day limitation in section 20.22(11) is directory rather than mandatory. Under that interpretation, a late arbitration decision would be valid unless the objecting party showed prejudice from the delay.
Although I believe the case is moot, if it is not, I would reverse and remand for the reasons in division II of the court’s opinion, returning the case to the same arbitration panel, subject to the provisions of section 20.22(6) regarding filling vacancies. I agree that the parties, in that event, should be authorized to amend their final offers.