¶ 1 The primary issue presented in this cumulative trauma injury case is whether the enactment of 85 O.S.2001 § 11(B)(5), which effectively prohibits apportionment by imposing sole liability on the covering insurer on the date of last exposure, should be applied retroactively. We hold that in cumulative trauma injury matters, where the date of injury pre-dates the effective date of the statute, October 23, 2001, § 11(B)(5) is inapplicable.
BACKGROUND
¶ 2 Claimant, Vicki H. Adkins, began working for Employer, John W. Ellis, M.D., on July 19, 1999. She sustained work-related, cumulative trauma injuries to her hands, arms and shoulders. Claimant filed her Form 3 on February 19, 2002, alleging the date of last exposure to be February 23, 2000 and continuing. The parties agree that Claimant first became aware of her work-related injury in October, 1999, and the trial judge found October 19, 1999, as the date of injury. This date has not been challenged.
¶ 3 CNA Insurance Company (CNA) provided the insurance coverage from Claimant’s first day on the job through December 31, 1999. On January 1, 2000, Employer’s carrier switched to Physicians Liability Insurance Company (PLICO), where coverage has remained at all times relevant since. At the time of trial, March 11, 2004, PLICO had provided all the medical treatment and benefits for Claimant’s injuries. PLICO successfully added CNA to the case in July, 2002.
¶ 4 The trial judge received medical expert evidence from Claimant, as well as CNA and PLICO. PLICO’s medical expert report opined that Claimant’s injuries occurred entirely before January 1, 2000, prior to PLI-CO’s assumption of coverage. CNA’s expert attributed half of the injuries to impairment during CNA’s coverage and the other half to impairment during PLICO’s coverage. Claimant’s expert did not opine as to apportionment of liability. After trial, the trial judge apportioned liability as 70% to PLICO and 30% to CNA.
¶ 5 Both insurers appealed to a three judge panel (Panel) of the Workers’ Compensation Court. 1 CNA, urging sole liability rests with PLICO, asserted that the Legislature abolished the apportionment of liability doctrine when it enacted 85 O.S.2001 § 11(B)(5) and replaced it with the last exposure rule. PLICO argued that while the trial judge was correct to apportion liability, the trial judge erred in, his apportionment percentages since the competent medical evi- *876 denee showed at most a 50/50 split of liability. The Panel reversed the portion of the trial judge’s decision apportioning liability and, apparently applying § 11(B)(5), found sole liability rested with PLICO.
¶ 6 PLICO appealed the Panel’s ruling. The Court of Civil Appeals (COCA), Division IV, reversed the Panel’s decision and remanded with instructions for the trial judge to enter judgment apportioning liability equally between CNA and PLICO. COCA held that § 11(B)(5) should not be applied retroactively and, as such, apportionment of liability in this case is proper. COCA remanded the action because it found the trial judge’s apportionment of 70/30 unsupported by any competent medical evidence and, instead, ordered an equal division of liability. Although we agree with the holding of the Court of Civil Appeals, Division IV, we vacate its opinion to reconcile an apparent conflict among divisions of COCA with respect to apportionment of liability and the application of § 11(B)(5). 2
I. TITLE 85 O.S.2001 § 11(B)(5) IS NOT TO BE APPLIED RETROACTIVELY.
¶7 The legal issue arises from the Legislature’s 2001 amendment of Section 11(B)(5) of the Workers’ Compensation Act, which reads in pertinent part:
When compensation is payable for an injury resulting from cumulative trauma, the last employer in whose employment the employee was last injuriously exposed to the trauma during a period of at least ninety (90) days or more, and the insurance carrier, if any, on the risk when the employee was last so exposed under such employer, shall alone be liable therefore, without right to contribution from any pri- or employer or insurance carrier.
Prior to the statute’s effective date of October 23, 2001, and on the date of injury in this case, the law allowed apportionment of liability between successive insurers in cumulative trauma cases.
See Parks v. Flint Steel Corp.,
A. History of Cumulative Trauma Cases
¶ 8 Historically, the date of awareness in cumulative trauma cases has been the determinative date in ascertaining disability.
Peabody Galion Corp. v. Workman,
¶ 9 While many argued this amendment signaled the end of the use of the awareness doctrine in all cumulative trauma matters, we disagreed and held that application of the last exposure rule was strictly limited to a determination of the relevant statute of limitations period.
Rankin v. Ford Motor. Co.,
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¶ 10 CNA and COCA, Division III, rely on
Southwest United Industries v. Polston,
¶ 11 A few months later, in
C.R. Industries v. Dorsey,
¶ 12 The date of Claimant’s injury is the critical date in determining the applicability of § 11(B)(5) to the instant matter. This is so because, generally, the law in effect at the time of the employee’s injury controls. See 85 O.S.2001 § 3.6(F)(“Benefits for an injury shall be determined by the law in effect at the time of the injury”). Because § 11(B)(5) was not in effect on the date of Claimant’s injury, October 19, 1999, we must determine if the Legislature intended it to have retroactive effect.
¶ 13 Statutes are typically not given retroactive effect unless the Legislature has made its intent to do so clear. Any doubts must be resolved against a retroactive effect.
Crawford v. Guardian Life Ins. Co.,
¶ 14. The right to compensation
and the obligation to pay
such benefits becomes vested and fixed by law at the time of the claimant’s injury. Such rights cannot be affected by after-enacted legislation.
Knott v. Halliburton Services,
¶ 15 With the enactment of § 11(B)(5), the last exposure rule governs and the insurer covering the risk on the date of last exposure is solely liable. Apportionment of liability with the previous insurer is now prohibited. However, on the date of injury here, as well as on the date PLICO, as the last insurer, *878 assumed the covered risk, § 11(B)(5) was not yet in existence and apportionment of liability was still proper. Because this statute affects the substantive rights of the parties, it cannot be given retroactive effect. Accordingly, we hold that under the facts presented in this case, apportionment of liability among CNA and PLICO was appropriate.
B. The Validity of COCA Opinions Addressing § 11(B)(5).
¶ 16 Because there are several COCA opinions in conflict with our holding here today, we now. address the continued viability of these decisions. COCA’s Division III first addressed the applicability of § 11(B)(5) in
Celestica Inc. v. Hines,
¶ 17 Celestica appealed, arguing that § 11(B)(5) should not be applied retroactively. Celestica maintained that the Rankin opinion established the date of awareness as the requisite date of injury in cumulative trauma cases and, since Lucent was the employer on this date, it should be the liable employer. COCA rejected this argument and held that “... the Legislature intended to make the last exposure doctrine apply to cumulative trauma cases, both for determination of the date of injury and for the determination of the liable employer in cases of multiple employers.” Celestica, Inc., supra, at ¶ 9. Because Celestica became Hines’ employer after the effective date of the statute, COCA reasoned it was on notice of the statute’s applicability. Id. at ¶ 10. The court also rejected the argument that the award should be apportioned according to the law in effect at the time of the injury, since the date of awareness also occurred after the effective date of the statute. Id. at ¶ 9.
¶ 18 The Celestica, Inc. case is distinguishable from the facts presented in the instant matter where the date of awareness precedes the statute’s effective date but the date of last exposure does not. On this basis alone, Celestica, Inc. is unpersuasive here. Nevertheless, because the date of awareness and date of last exposure apparently both occurred after the enactment of § 11(B)(5), we agree its application in Celestica, Inc. seems proper. However, we reject the assertion in Celestica, Inc. that since the last employer was already on the risk when § 11(B)(5) was enacted, such employer could properly be charged with notice of that statute. Simply because an employer was on the risk at the time of the enactment of § 11(B)(5) does not in itself require the applicability of that statute. To the contrary, as we have previously held herein, where the date of the injury precedes the enactment of § 11(B)(5), apportionment would still be appropriate and a vested right of the subsequent employer which could not be retroactively divested. While the date of injury in Celestica, Inc., apparently came after the enactment of § 11(B)(5), as discussed above, later COCA opinions applied this faulty premise to their own case-specific facts and, therefore, we expressly repudiate this reasoning. 5
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¶ 19 CNA also cites
Parkhurst v. City of Tulsa,
¶20 Finally, in the most recent COCA opinion to address § 11(B)(5),
Energy Exchanger Co. v. Hill,
C. Determination of Apportionment.
¶21 As mentioned previously, the trial court apportioned 70% of the liability to PLI-CO and 30% of the liability to CNA. No explanation was provided as to how the trial court reached this determination. At trial, PLICO denied any responsibility to Claimant. On appeal, PLICO argues that the only medical evidence addressing apportionment, aside from its own expert report which assigned all liability to CNA, is the report of CNA’s medical expert apportioning liability 50-50 as to each insurer. Claimant’s expert report did not discuss apportionment. PLI-CO urges that, based on the medical evidence presented by the parties, liability should be shared equally by PLICO and CNA. COCA agreed and remanded the matter with instructions to enter judgment apportioning liability equally between CNA and PLICO. COCA’s instruction is vacated. We remand the cause back to the trial court for an on-the-record assessment of apportionment that is based upon competent probative medical evidence as to the degree of impairment caused during each insurer’s coverage period.
Hammons v. Oklahoma Fixture Co.,
CERTIORARI PREVIOUSLY GRANTED; COURT OF CIVIL APPEALS’ OPINION VACATED; JUDGMENT OF THE TRIAL COURT AFFIRMED IN PART, REVERSED IN PART AND REMANDED WITH INSTRUCTIONS.
Notes
. Claimant did not appeal the apportionment ruling, leaving this dispute to the insurance carriers. Claimant did initially appeal the rate of her permanent partial disability compensation, see Case No. 101,415, but she has since dismissed that case and the trial court’s decision with respect thereto remains intact.
. The following COCA cases have addressed the application of § 11(B)(5) and will be discussed further herein:
Celestica Inc. v. Hines,
. Laws 1985, c. 266, § 4, eff. Nov. 1, 1985.
. It is important to point out that Polston, a case decided less than two years after Rankin, did not even mention the Rankin case, much less overrule it.
.
KECO, Inc. v. Hayward,
Less than two months later, the same COCA, Division III, decided
Anderson Mechanical, Inc. v. Spiegel,
. Likewise, in
OCT Equipment, Inc. v. Ferrell,
