OPINION
(Assigned).
This mandamus proceeding arises out of a negligence suit filed by Elizabeth Gaetjen (“Gaetjen”) against her employer, Luby’s Cafeterias, Inc. (“Luby’s”), after Gaetjen was sexually assaulted in the workplace by a fellow employee. The relator, Luby’s, contends the trial court abused its discretion by refusing to abate the negligence trial until the Texas Workers’ Compensation Commission decides whether Gaetjen, the real party in interest, sustained a compensable injury. See generally Tex. Lab.Code Ann. Ch.402 (Vernon 1996). We agree and conditionally grant mandamus relief.
BACKGROUND
In April 1995, Gaetjen, who is mildly retarded, was employed as a bus person at a Luby’s Cafeteria in Houston, Texas. At that time, Gaetjen was sexually assaulted over the course of three days by a fellow employee, Antonio Aguirre. Following the incidents, Gaetjen filed a complaint with the Houston Police Department and a workers’ compensation claim. On May 15, 1995, Luby’s workers’ compensation carrier, TIG Premier Insurance Company (“TIG”), denied the claim on the ground that Gaetjen did not sustain a compensable injury. Gaetjen did not seek review of this determination. See Tex. Lab. Code Ann. Ch. 410 (Vernon 1996). In August 1996, Aguirre was convicted of sexually *815 assaulting Gaetjen and sentenced to five years in the Texas Penitentiary.
In April 1997, almost two years after the incident, Gaetjen filed the underlying negligence suit against Luby’s. On December 10, 1997, after discovery revealed information about Aguirre’s past criminal record and after urging by Luby’s counsel, TIG reopened Gaetjen’s claim. The parties proceeded to a benefit review conference and then a contested case hearing. See Tex. Lab.Code Ann. §§ 410.021, 410.024, 410.151 (Vernon 1996). On June 21, 1998, the hearing officer found Gaetjen sustained a compensable injury and ordered TIG to pay benefits. On July 7, 1998, Gaetjen appealed this ruling. See Tex. Lab.Code Ann. § 410.202 (Vernon 1996). Ten days later, Luby’s requested an abatement of the September 8, 1998 trial, pending a final decision by the Commission. Luby’s did not obtain a ruling on its motion.
On August 21, 1998, the appeals panel reversed the hearing officer’s decision and remanded the case for a determination of whether the assaults were motivated by personal reasons and not directed to Gaetjen as an employee or because of her employment. See id. § 406.032(1)(C). On August 27, 1998, Luby’s again requested an abatement of the trial pending a final decision by the Commission. On September 4, 1998, the trial court denied Luby’s motion and retained the ease on its trial docket. On September 10, 1998, Luby’s filed this mandamus proceeding. Since the filing of Luby’s petition, the hearing officer has determined on remand that Gaetjen’s injury is compensable. At oral argument, Gaetjen’s counsel acknowledged there will be an appeal of the hearing officer’s decision.
ANALYSIS
Mandamus relief is available if the trial court violates a duty imposed by law or clearly abuses its discretion, either in resolving factual issues or in determining legal issues, when there is no other adequate remedy by law.
See Walker v. Packer,
Relying on
Mantas v. Fifth Court of Appeals,
The supreme court held that the defendant was entitled to mandamus relief, concluding that “it makes no sense for the court of appeals to expend its resources and require the parties to expend theirs on an appeal which may be moot.” Id. at 659. The court also concluded that “a ruling on the merits of the appeal before judgment is rendered in the enforcement suit would inject needless uncertainty and confusion into the issues surrounding the settlement.” Id. Finally, the court determined that the defendant lacked an adequate remedy by appeal because “if the agreement is upheld, [he] will have lost much of the settlement’s benefit if he has been required to expend time and resources in prosecuting the appeal.”
We believe the reasoning in Mantas is equally applicable here. Claiming that Ga-etjen has sustained a compensable injury, Luby’s has asserted the exclusive remedy defense to Gaetjen’s negligence claim. See Tex. Lab.Code Ann. § 408.001(a) (Vernon 1996) (“recovery of workers compensation benefits is the exclusive remedy of an employee covered by workers’ compensation coverage”). Hence, a jury would have to first decide the compensability issue before it could consider the negligence issue. Whether Gaetjen’s injury is compensable, however, is a matter within the primary jurisdiction of the Commission.
“Primary jurisdiction is a judicially ■ created doctrine of abstention, whereby a court that has jurisdiction over a matter nonetheless defers to an administrative agency for an initial decision on questions of fact or law within the peculiar competence of the agency.”
See State Bar v. McGee,
Accordingly, it would be pointless for the court and parties in the underlying suit to expend their resources on a trial until the Commission first decides the compensability issue. Gaetjen argues that the court and the parties have already expended substantial resources in discovery. That discovery will not he for naught. Luby’s is requesting an abatement of the trial only until the Commission makes a final decision. It is not requesting an abatement until a de novo appeal is decided by a district court. See Tex. Lab.Code Ann. § 410.251 (Vernon 1998). Thus, any such appeal of the Commission’s decision on the compensability issue can be consolidated with the underlying lawsuit and the discovery that has occurred to date can be used in that suit.
*817 Furthermore, a judgment rendered in the underlying negligence suit before a final decision by the Commission, “would inject needless uncertainty and confusion into the issues.” There potentially could be a judgment awarding Gaetjen damages and a final agency decision awarding her workers’ compensation benefits. The effect of the trial court’s judgment on a de novo appeal is unclear. Undoubtedly, subjecting the workers’ compensation subscriber to a negligence trial and a potential judgment before the Commission decides whether the employee’s injury is compensable will inject needless uncertainty and confusion into the issues surrounding both proceedings. Gaetjen argues there will be no confusion of issues because Ruby’s is not a party to the Commission proceedings. This ignores the fact that the compensation carrier is acting on Ruby’s behalf in those proceedings, which involve some of the same issues, facts and witnesses as the underlying trial.
Because the compensability of Ga-etjen’s injury is clearly an issue within the exclusive primary jurisdiction of the Commission, the trial court had no choice but to abate the negligence trial pending a final decision by the Commission. The court’s failure to do so was a misapplication of the law and an abuse of discretion.
See Walker,
Gaetjen argues that mandamus relief is improper because she filed her lawsuit before the commencement of Commission proceedings and therefore, the trial court has dominant jurisdiction over the Commission. Under the principle of dominant jurisdiction, the court in which suit is first filed acquires dominant jurisdiction to the exclusion of
other coordinate courts. See Clawson v. Millard,
Finally, Gaetjen argues there was no abuse of discretion because Ruby’s did not timely seek abatement. A party must raise a plea in abatement in a timely manner or it is waived.
See Wyatt v. Shaw Plumbing Co.,
Although TIG reopened Gaetjen’s claim at Luby’s urging in December 1997, it was not until Gaetjen appealed the hearing officer’s finding of compensability six months later, that Luby’s realized Gaetjen did not want compensation and that the Commission proceedings would possibly continue into the trial. While Luby’s promptly requested an abatement, it did not obtain a ruling, but instead waited more than a month to file its second request and secure a ruling. Gaetjen makes much of the fact that Luby’s first request was days before the first trial setting. The court, however, had already reset the trial for September 1998 when Luby’s made its request. Although Luby’s second request was within days of the second trial date, the request was a timely response to the decision of the appeals panel to remand the case for another contested case hearing. Under the circumstances, we do not believe that the delay in this case amounts to waiver.
Because the trial court abused its discretion by refusing to abate the trial until the Commission makes its final decision, Luby’s is entitled to mandamus relief. Accordingly, the trial court should vacate is September 4, 1998 order denying abatement and enter the appropriate order. Writ will issue if the trial court fails to comply.
Notes
. Relying on two cases from this Court, Luby’s asserts that mandamus relief is appropriate here to preserve the structure of the statutory process.
See Kimball Homes,
. There is an exception to primary jurisdiction when an agency is exercising authority beyond its statutorily conferred powers.
Television Cable Service, Inc. v. Bryant,
