OPINION
Truсk Drivers Local No. 164 (“Union”) appeals from the district court’s grant of summary judgment in favor of Allied Waste Systems, Inc. (“Allied”), which vacated an arbitrator’s award ordering reinstatement of Grievant Keith Miller (“Miller”). On appeal, the Union argues that the district court erred in vacating the arbitrator’s award. At oral argument, both parties agreed that this case is directly impacted by our recent
en banc
decision in
Michigan Family Resources, Inc. v. Service Employees International Union,
I.
Allied is engaged in the business of collecting and disposing of nonhazardous solid waste, and the Union represents Allied’s employees at its Adrian, Michigan, location. Allied acquired its Adrian, Michigan, facilities frоm Laidlaw Waste Services in 1999, and for a few years after this acquisition, Allied and the Union operated under the predecessor collective bargaining agreement negotiated between Laidlaw and the Union. In May 2003, the Union and Allied entered into a new agreement, which borrowed in large part from the language of the predecessor agreement.
Several provisions of the May 2003 agreement are relevant to our review of the arbitrator’s award. Article 18 of that agreement reserves management rights to Allied, stating:
“Except as expressly and specifically limited or restricted by a provision of this Agreement, the Company has and shall retain the full right of management and direction of the Company and its operations. Such rights and responsibilities of management include, but are not limited to, the right ... to discharge and otherwise discipline employees for just cause.”
Article 8 governs the employer’s right to discharge or suspend employees. Section 8.1 states that “[t]he right to discharge and the maintenance of discipline shall be the exclusive right and responsibility of the Company except that the Company shall not discharge or otherwise discipline an employee without just cause.” Section 8.2 prescribes the allowable discipline for a violation of the “Company’s Mandatory Safety and Work Rules” — distinguishing between a violation of Section 1 of those rules, whiсh permits Allied to discharge the employee immediately, and a violation of Section 2 of those rules, which requires Allied to give the employee at least one warning notice prior to discharge.
Article 9 governs the arbitration and grievance procedures. Section 9.4 outlines the process and procedures by which arbitration is to be conducted, and Sections 9.4(D), 9.4(F), and 9.4(G) define the scope of the arbitrator’s power. Section 9.4(D) states:
[T]he arbitrator shall have no power or authority to amend, alter[,] or modify this Agreement, but shall be limited to deciding whether or not a violation of its expressed terms has been committed. ... The arbitrator shall have no power to substitute his disсretion for that of the Company in cases where the Company has retained discretion or the right to act under this Agreement.
Section 9.4(F) provides:
The decision of the arbitrator ... shall be final and binding upon the parties when rendered upon a matter within the authority of the arbitrator and within the scope of the matters subject to arbitration provided in this Agreement, and shall be void insofar as the decision ex *214 ceeds the authority of the arbitrator or passes upon matters not expressly made subject to arbitration under the terms of this Agreement.
And most relevant to this dispute, Section 9.4(G), states: “It is understood and agreed that the degree of discipline up to and including discharge imposed for just cause shall be in the sole discretion of management and shall not be subject to modification by an arbitrator.” The agreement also contains a “zipper clause,” which states that the terms of the enacted agreement “shall supersede and render ineffective any past practices, addendum, letters of understanding, oral or written agreement as may now exist or as may have existed.”
On April 4, 2005, Allied employee and Union bargaining-unit member, Keith Miller, drove a garbage collection route normally assigned to another driver. While backing his truck down the left lane of a dead-end residential street, Miller “hooked” a low-hanging overhead wire, pulling it from a nearby house. Miller immediately informed dispatch of this incidеnt; Allied supervisors arrived on the scene and completed a “Notice Form” summarizing the accident. The supervisors observed that Miller was backing down the wrong side of the street, that Miller violated Allied’s “Zero Tolerance Safety Guidelines,” and that Miller violated Allied’s “Employee Safe Driving and Safe Practices.”
On the same day as the accident, Allied suspended Miller without pay pending further investigation. On the following day, Allied terminated Miller because, according to Allied, he violated a rule in Section 1 of the Company’s Mandatory Safety and Work Rules, which permitted immediate discharge under Section 8.2 of the collective bargaining agreement. Two days later, Miller filed a grievance, contending that he did not violate a Section 1 rule and, consequently, that Allied should reinstate him with back pay. Within a week, the company denied Miller’s grievance, and the parties proceeded to arbitration.
At arbitration, the parties vehemently disputed which set of rules comprised the “Company’s Mandatory Safety and Work Rules” referenced in Section 8.2 of the agreement. The parties conceded that during negotiation of the current agreement, neither side brought up Section 8.2, which was the primary cause of this contractual ambiguity. Allied argued that it had been using two sets of rules — the “Employee Safe Driving and Safe Practices” handbook and the “Zero Tolerance Safety Guidelines” — and that these rules were the ones referenced in Section 8.2 of the agreement. The Union contended that the applicable rules were those that were actually entitled “Mandatory Safety and Work Rules” and were attached to the predecessor agreement. The arbitrator sided with the Union, reasoning that Allied’s proposed rules had “a different nomenclature than in [Section 8.2 of the agreement] and they ha[d] a different structure — i.e., no Section 1 or Section 2.” After determining that the Union’s proposed rules applied, the arbitrator concluded that Miller’s conduct violated Section 2 of those rules — not Section 1 as alleged by Allied — and that the collectivе bargaining agreement required Allied to give Miller at least one warning notice prior to discharge.
The arbitrator then analyzed Miller’s termination assuming that Allied’s proposed rules applied. The arbitrator reasoned that even those rules contemplate degrees of discipline and do not automatically mandate discharge. For example, the Employee Safe Driving and Safe Practices handbook permits “disciplinary action up to and including immediate discharge,” *215 and the Zero Tolerance Safety Guidelines state that Allied generally will conduct “progressive discipline” but that an employee will be immediately discharged if his improper conduct causes an “аccident.” After acknowledging these degrees of discipline, the arbitrator determined that even though Miller violated some of Allied’s proposed rules, his termination was inappropriate because this “incident involved an accident only in an obviously hypertechnical sense: the telephone lines had drooped far below standards, and [Allied] incurred no loss as a result of the incident.” The arbitrator, in short, determined that Miller’s discharge was unwarranted under either the Union’s or Allied’s proposed rules.
Allied cautioned the arbitrator that the collective bargaining agreement severely circumscribed his authority to review or modify the reasonableness of Miller’s discipline, emphasizing Section 9.4(G)’s admonition that “the degree of discipline ... imposed for just cause shall be in the sole discretion of management and shall not be subject to modification by an arbitrator.” The arbitrator, however, perceived an internal tension between Section 9.4(G), which, according to Allied, limited the arbitrator’s authority to review or modify the degree of discipline imposed by management, and Section 8.1, which prohibited Allied from disciplining an employee without just cause. The arbitrator attempted to reconcile this tension, reasoning:
The term “just cause” entails a two-prong inquiry. First, did the Grievant violate an Employer rule or policy which warrants discipline? If the answer to the first is in the affirmativе, it is then necessary to consider whether the discipline imposed is reasonable under the circumstances of the matter before the Arbitrator. The severity of the discipline is an integral part of the inquiry.
The arbitrator concluded that because the just-cause inquiry required him to consider the reasonableness of a grievant’s discipline, the agreement implicitly authorized him to evaluate the severity of Miller’s discipline.
The arbitrator then proceeded to his resolution of the grievance, reiterating that Miller had violated Section 2 of the Union’s proffered rules as well as various provisions of Allied’s proffered Employee Safe Driving and Safe Work Practices handbook. The аrbitrator made two distinct findings regarding just cause. First, he held that Allied lacked just cause to terminate Miller because termination was not “reasonable” and it “exceeded the penalty allowed” in Section 8.2 of the agreement. Second, he found that Allied had just cause to issue a written warning to Miller because Section 8.2 of the agreement permitted a warning notice for a violation of Section 2 of the Mandatory Safety and Work Rules. The arbitrator’s award stated: “The Grievant’s termination is set aside and, in lieu thereof, a Written Warning may be issued. The Grievant is to be reinstated to his former position with back pay and benefits.... ”
Approximately two weeks later, the Union filed suit in district court, seeking to сompel Allied to comply with the arbitrator’s decision, and asking for additional back pay for the period following the arbitrator’s award. Allied filed its answer and counterclaim, asking the court to vacate the arbitrator’s award. The parties filed cross-motions for summary judgment. The district court denied the Union’s motion, granted Allied’s motion, and vacated the arbitrator’s decision. The court rejected the arbitrator’s conclusion that the rules referenced in Section 8.2 were the “Mandatory Safety and Work Rules” proposed by the Union, rather than the two sets of rules presented by Allied. The *216 court reasoned that because the Union’s proffered rules were part of the prior collective bargaining agreement, the zipper clause, which stated that the new agreement would supersede any past practices or agreements, voided the application of those rules. The court then, apparently relying on Section 9.4(G) of the agreement, held: “[I]n altering the discipline that was given to Miller, the arbitrator exceeded the scope of his authority, and, in doing so, he violated the express terms of the Collective Bargaining Agreement.” The Union filed a motion for reconsideration pursuant to Fed.R.Civ.P. 59(e), which was denied by the district court, and the Union filed a timely notice of appeal to this court.
II.
Although we review the district court’s grant of summary judgment
de novo, Gage Prods. Co. v. Henkel Corp.,
At the outset, we note that the district court did not have the benefit of our recent decision in Michigan Family Resources. The parties, however, did, but their briefs do not discuss the case, although they both acknowledged at oral argument that it directly impacts the issues before this court. The parties have therefore failed to raise their arguments in terms of the three questions of procedural aberration. Moreover, the Union curiously framed most of its arguments as a challenge to the district court’s reasoning, rather than focusing on the analysis in the arbitrator’s decision. In a situation such as this, where we are reviewing de novo the district court’s decision to vacate an arbitrator’s award, the focus is on the arbitrator’s analysis, not that of the district court. We will recast the parties’ arguments, placing the proper focus on the arbitrator’s decision and the analytical approach outlined in Michigan Family Resources.
Under even the most generous reading of Allied’s brief, it does not allege that the arbitrator engaged in fraud, labored under a conflict of interest, or otherwise acted dishonestly; thus we need not consider this sort of рrocedural aberration. But Allied’s arguments impact the remaining two questions — whether the arbitrator ex *217 ceeded his authority and whether the arbitrator was arguably construing or applying the contract — and we will consider both of these issues.
We begin with the question of whether the arbitrator exceeded his authority in issuing his decision. Allied argues that the arbitrator exceeded his authority by modifying Miller’s discipline from a termination to a written warning because the collective bargaining agreement prohibited the arbitrator from modifying the severity of the discipline imposed. This argument certainly implies that the arbitrator exceeded the scope of his authority under the agreement, but in
Michigan Family Resources
we severely curtailed the “scope of authority” concept. In that case, we stated: “An arbitrator does not exceed his authority every time he makes an interpretive error; he exceeds that authority
only
when the collective bargaining agreement does not commit the dispute to arbitration.”
Mich. Family Res.,
We next consider whether the аrbitrator was arguably construing and applying the agreement, or whether he ignored the terms of the agreement and “dispense[d] his own brand of industrial justice.”
See United Steelworkers of Am. v. Enter. Wheel & Car Corp.,
At arbitration, the parties disputed which work rules were referenced in Section 8.2 of the collective bargaining agreement. The arbitrator reasoned that the Union’s rules must apply because Section 8.2 refers to a set of rules divided into two sections and only the Union’s rules were divided in that manner. The district court objected to the arbitrator’s adoption of the Union’s rules, concluding that the Union’s rules, which were originally attached to the predecessor collective bargaining agreement, were superseded under the zipper clause in the current agreement. Even if we were to agree with the district
*218
сourt and conclude that the arbitrator incorrectly determined that the Union’s rules were those referenced in Section 8.2,
1
we find this to be a classic instance of labor-contract interpretation. “It is the arbitrator’s construction which was bargained for; and so far as the arbitrator’s decision concerns construction of the contract, the courts have no business overruling him because their interpretation of the contract is different from his.”
Enter. Wheel & Car Corp.,
The major issue in this case — indeed, the primary basis upon which the district court vacated the arbitrator’s award — is whether the arbitrator’s award violated Section 9.4(G) of the agreement. Section 9.4(G) states that “the degree of discipline ... imposed for just cause shall be in the sole discretion of management and shall not be subject to modification by an arbitrator.” Allied implored the arbitrator to recognized that Section 9.4(G) prohibited him frоm even considering — not to mention altering — the level of discipline imposed against Miller. The arbitrator, however, determined that Section 9.4(G) could not be read so broadly because such an expansive reading conflicted with other contractual provisions that expressly and unambiguously prohibited Allied from “discharging] or otherwise disciplining] an employee without just cause.” The arbitrator reasoned that the just-cause inquiry required him first to evaluate whether the grievant violated a work rule and then “to consider whether the discipline imposed [was] reasonable under the circumstances.” He thus concluded that, notwithstanding Allied’s expansive reading of Section 9.4(G), the collective bargаining agreement authorized him to consider the degree of discipline imposed by Allied.
Following arbitration, Allied thought that the arbitrator had violated Section 9.4(G) in another way, namely, by modifying the degree of discipline imposed after he expressly found just cause to discipline Miller (i.e., issue a written warning). The district court agreed, finding that “the arbitrator ... violated the express terms of the [collective [bargaining [a]greement” by “altering the discipline that was given to Miller.” Allied contends that Section 9.4(G) clearly prohibits the arbitrator from modifying the degree of discipline whenever he finds that any degree of discipline (e.g., written warning, suspension, termination) would be supported by just cause. Thus, according to Allied, the arbitrator violatеd Section 9.4(G) because once he found just cause to issue a written warning, he was without authority to modify the degree of discipline selected by Allied (i.e., termination).
*219 The Union argues that Allied’s broad interpretation of Section 9.4(G) conflicts with Section 8.2 of the agreement. Section 8.2 prescribes the allowable discipline for an employee’s violation of the Mandatory Safety and Work Rules — distinguishing between a violation of Section 1 of those rules, which permits Allied to discharge the employee immediately, and a violation of Section 2 of those rules, which requires Allied to give the employee at least one warning notice prior to discharge. The Union contends that Allied’s construction of Section 9.4(G) effectively negates Section 8.2’s distinction in the level of allowable discipline for different work-rule violations by stripping the arbitrator of authority to enforce that distinction. For example, an arbitrator who found, as the arbitrator here did, that the grievant violated a Section 2 rule, rather than a Section 1 rule, would be prohibited from reducing the grievant’s discipline to a written warning, even though Section 8.2 of the agreement expressly states that Allied is permitted to impose only a written warning against a first-time offender of those rules. The Union argues that Section 9.4(G) cannot be interpreted in a manner that effectively nullifies Section 8.2. In essence, then, the Union believes that 9.4(G), as properly understood, restricts the arbitrator’s authority to modify the degree of discipline only where he finds that the particular degree of discipline actually imposed by the employer was supported by just cause. Under this interpretation, the arbitrator here did not violate Section 9.4(G) because he found no just cause to support Miller’s termination (i.e., the particular degree of discipline actually imposed by the employer) and therefore was not limited by Section 9.4(G)’s purported restriction on his authority.
We find that Section 9.4(G) is no2 clear on its face and that it can reasonably be interpreted as urged by either Allied or the Union.
2
More importantly, the arbitrator, when construing the limitations on his authority in Section 9.4(G) (although he did so in response to a slightly differеnt argument), was indisputably construing and applying the contract. “He referred] to, quote[d] from[,] and analyze[d] the pertinent provisions of the agreement, and at no point [did] he say anything indicating that he was doing anything other than trying to reach a good-faith interpretation of the contract.”
See Mich. Family Res.,
*220
We acknowledge that, by including Section 9.4(G) in the agreement, Allied attempted to “limit the arbitrator’s authority to fashion a remedy by careful drafting of the collective bargaining agreement.”
See Kar Nut Prods. Co. v. Int’l Bhd. of Teamsters,
No. 92-2084,
III.
The Union requests that we award Miller back pay from the date of the arbitrator’s award until the date of Miller’s eventual reinstatement, which, at least as of the date of oral argument in this matter, had not yet to occurred.
See Lynchburg Foundry Co. v. United Steelworkers of Am., Local 2556,
Should it be determined that an employee, other than probationary employee was disciplined or discharged without just cause, he shall be restored to his former status; provided, however, that the arbitrator shall not award back pay for a period exceeding ninety (90) days and provided further that the Company shall have the right to credit against any back pay awarded any earnings, compensation, or enumeration [sic] received by the employee from any source whatsoever including unemployment compensation and worker’s [sic] compensation payments during the period involved.
Miller was discharged on April 5, 2005, and the arbitrator ordered him reinstated on August 31, 2005. The arbitrator’s award stated that “[Miller] is to be reinstated to his former position with back pay and benefits subject to the limitations found in Article 9.4(G).” Pursuant to the limitations on back pay in Article 9.4(G), Miller would have received back pay for only 90 of the more than 145 days between his discharge and the arbitrator’s decision. Allied further argues, citing
Yamaha Int’l Corp. v. United Furniture Workers of America, AFL-CIO,
In
Yamaha I,
the arbitrator awarded the union grievant reinstatement
without
back pay and Yamaha filed an action in the district court to vacate the award. The district court ordered the award enforced, and additionally ordered back pay from the date of the award' to the date of the district court’s entry of judgment. The Union’s brief on appeal included a request to enlarge the district court’s judgment to include back pay for a period subsequent to the district court’s order; we affirmed the district court but did not address the Union’s request.
See Yamaha Int’l Corp. v. United Furniture Workers of America,
More recently, this issue was addressed in
Mansfield Plumbing Prod. v. Teamsters, Chauffeurs & Helpers Local Union No. 10,
The district court separated into several discrete periods the time for which the Union sought additional back pay and held — for reasons not material to the instant case — that it was without jurisdiction to award additional back pay for all but one of them. The court held, however, that additional back pay was appropriate for the four-month period from the second arbitration award ordering reinstatement until the actual reinstatement of the griev-ant. The district court summed up the situation before it and sensibly held that
[e]ven though Mansfield was challenging both arbitration orders in this court, it was legally obligated to reinstate and pay Martin. It did not do so. To hold otherwise would [ ] provide a great incentive for employers to challenge every arbitration decision virtually cost-free, since even if they lost, they would be saved from paying wages for the pen-dency of the appeal.
Id. at *7. In reaching its conclusion, the district court also held that
[a]n award of back pay for the four months between the second arbitration decision and reinstatement does not go beyond the terms of the CBA, as Mansfield contends. To the contrary, back pay is consistent with and directly results from the CBA.... If an award is to be final and binding, the employer is required to reinstate the employee and pay him. If they fail to reinstate him, they remain obligated to pay him, unless the arbitration award is overturned by a court of law.
Id.
We think that Mansfield is correctly decided, 5 and for the reasons stated by the district court in that case, we conclude, first, that the language on which Allied relies in Article 9.4(G) of the CBA here limits only the arbitrator’s ability to award back pay, and does not limit the ability of the court to do so. We further conclude that additional back pay from the time of an arbitrator’s reinstatement award until the time that a grievant is reinstated is an appropriate judicial remedy. Finally, however, because we do not have before us the necessary facts to determine the amount of the back pay due to Miller, we must remand this matter to the district court for further proceedings consistent with this opinion.
IV.
For the foregoing reasons, we REVERSE the оrder of the district court granting summary judgment to Allied and REMAND to the district court with instructions to reinstate the arbitrator’s award, and for the limited purpose of calculating the appropriate award of back pay.
Notes
. Although it is not necessary to our resolution of this suit, we do not agree with the district court’s analysis on this issue. The zipper clause is inapplicable when determining which rules should apply under Section 8.2. The rules referenced in Section 8.2— whichever set of rules the arbitrator determines those to be — have been expressly incorporated into the new agreement and therefore are not superseded as provided in the zipper clause. The arbitrator recognized that the zipper clause did not impact this analysis, and we agree with his conclusion.
. Counsel for Allied, in what may have been a "Freudian slip," acknowledged at oral argument that Section 9.4(G) "maybe is a little bit ambiguous,” and later stated, in complete contradiction, that "there is no ambiguity” because this provision consists of “plain language.” As counsel for the Union aptly recognized, however, Allied cannot "have it both ways,” and, given these alternatives, we con-elude that there is some ambiguity in Section 9.4(G).
. Allied also contends that the arbitrator’s decision should be vacated because he improperly reduced Miller’s discipline based on "general considerations of fairness and equity instead of the precise terms of the agreement.”
See Cement Divs., Nat'l Gypsum Co. v. United Steelworkers, Local 135,
.
This case came before us on several occasions. For ease of reference, we refer to
Yamaha Int’l Corp. v. United Furniture Workers of America,
. We note with some concern the district court's apparent misunderstanding of the result we reached in Yamaha II. but we note as well that this error did not affect the district court’s overall analysis.