with whom OPALA, J. joins, dissenting.
T1 Three prior opinions of the Court of Civil Appeals have addressed aspects of the same litigation. In Dean v. Special Indem. Fund (Dean I), 1998 OK CIV APP 30, 956 P.2d 945, the appellate court held that no reviewable issue was presented when the Workers' Compensation Court left open the issue of who would be included as members of certain classes and the method of determining the appropriate compensation for each class member. Dean II, Multiple Injury Trust Fund v. Dean, 2001 OK CIV APP 30, 24 P.3d 861, rehearing denied (2000), cert. denied (2001), held that; 1) the Workers' Compensation Court had jurisdiction to entertain a class action to enforce a specifically granted right; 2) the one-year statute of limitations applicable to civil actions was not applicable to the claimants' action; 8) the Fund's insolvency did not prevent an award; and 4) the Fund's difficulty in paying awards was insufficient cause to grant an exception to the rule that partial payments of judgments are applied first to interest and then to principal. Finally, in Dean v. Multiple Injury Trust Fund (Dean III), 2003 OK CIV APP 34, 67 P.3d 356, rehearing denied (20083), cert. denied (2003), the Court of Civil Appeals determined that judgments against the Fund for accrued unpaid portions of a permanent total disability award could be certified to district court.
T2 The two causes consolidated here represent the culmination of a lengthy litigation process which began in 1998 and remains unresolved in 2006. Most certainly, the litigants are hopeful that the majority opinion will be the final pronouncement in the causes and that they may now have some assurance of the collection of unpaid awards and the interest thereon. Nevertheless, no such confidence can arise from the majority's decision. At the very least, the majority writing appears internally inconsistent. Furthermore, it plays havoc with well-settled principles of workers' compensation law. For these reasons, I dissent.
T3 1) The majority opinion appears internally inconsistent in its treatment of the doctrine of the settled law of the case.
4 The majority opinion appears internally inconsistent in that it refuses to apply the settled-law-of-the-case doctrine to Dean IIL. Nevertheless, the majority holds that the same doctrine is applicable to Dean IL. Curiously enough, however, the settled-law-of-the-case doctrine is utilized to support a proposition which the majority admits Dean II does not directly address.1
4 5 At best, all one can "presume" from the majority opinion is that, based on the settled law of the case, individuals filing Form 9s for a material increase in the Workers' Compensation Court successfully opted out of the *1107class. However, based on the refusal to apply the doctrine to Dean III, the same individuals will be unable to certify judgments against the Multiple Injury Trust Fund to the district court.
T6 In reaching its result, the majority ignores well-settled principles of workers' compensation law.
T7 Most disturbing is the majority's infidelity to a statutorily imposed 2 and a long-recognized mandatory 3 rule of workers' compensation law-that benefits for an injury shall be determined by the law in effect at the time of injury.4 Consistent with the rule, this Court has refused to apply legislative changes retroactively.5
8 The rules have their genesis in a recognition that compensation statutes, creating rights and obligations between the employer and employee, are a part of the contract of employment which become vested upon the injurious occurrence.6 No subsequent amendment can operate retroactively to affect, in any way, the rights and obligations which are fixed.7 Both rules have been applied specifically to the respondent, Multiple Injury Trust Fund (Fund).8
T 9 The majority states that "[blefore 1994, when § 42 was amended, nothing in that statute proscribed certification of an award against the Fund." It then proceeds to apply the 2001 version of the statute, which contains the same language considered, to reach its determination that the Fund is exempt from certification of awards against it. In so doing, the majority affects claimants who were awarded benefits against the Fund as early as January 1, 1987.
10 Dean II, which the majority upholds on the basis of the settled law of the case, specifically provides at 1 2:
*1108"In Claimants' action for interest on unpaid claims against the Fund they sought certification of a class of all claimants who have been awarded benefits against the Fund since January 1, 1987 and whose awards have not been paid. The Workers' Compensation Court entered its order June 22, 1995, in which it certified as a class all claimants who had been awarded benefits against the Fund since January 1, 1987 and whose elaims remained unpaid."
To reach this result, the majority ignores mandatory statutory language providing that the law in effect at the time of the injury shall govern workers' compensation claims.9 By implication, it overrules a line of our jurisprudence dating from 1925 to the present in which the Court has faithfully applied the rule.10 Finally, it ignores precedent prohibiting the retrospective application of workers' compensation statutes.11
CONCLUSION
11 The majority opinion appears internal-Ty inconsistent. It leaves the bench, the bar and the litigants with a muddled analysis of where, when and how the settled-law-of-the-case doctrine applies. Furthermore, it ignores a statutory mandate of the Legislature relating to the application of workers' compensation statutes and impliedly overrules numerous cases of this Court. Because I cannot accede to an analysis which so obfuscates and eviscerates Oklahoma workers' compensation law, I dissent.
. The majority opinion provides in pertinent part at p. 1105:
"... The issue of interest was determined on January 29, 1997. Multiple Injury Trust Fund v. Dean, 2001 OK CIV APP 30, ¶ 3, 24 P.3d at 863.
The issue of liability in this case was over the amount of interest due the class on their judgments. For potential members of the class to be excluded from the class, provided they did not receive individual notification, they must have requested exclusion from the class before January 29, 1997, or they must have commenced an individual action for interest on their judgments before that date. The 2001 Dean case did not address who could be excluded from the class. Nevertheless, the ruling of the Court of Civil Appeals, which sustained the make-up of the class as determined by the workers' compensation court, set the boundaries of the types of actions that would allow exclusion from the class. Pursuant to § 23(C)(2)(c), those claimants must have commenced an action requesting interest on their judgments before January 29, 1997, to be excluded from the class. This is the settled law of the case...."
. Title 85 0.$.2001 § 3.6(F) provides:
"Benefits for an injury shall be determined by the law in effect at the time of injury; benefits for death shall be determined by the law in effect at the time of death."
. Generally, the use of "shall" signifies a legislative command. McClure v. ConocoPhillips Co., 2006 OK 42, ¶ 18, 142 P.3d 390; Barzellone v. Presley, 2005 OK 86, ¶ 35, 126 P.3d 588; Cox v. State ex rel. Oklahoma Dept. of Human Services, 2004 OK 17, ¶ 21, 87 P.3d 607. Nevertheless, there may be times when the term is permissive in nature. Minie v. Hudson, 1997 OK 26, ¶ 7, 934 P.2d 1082; Texaco, Inc. v. City of Oklahoma City, 1980 OK 169, ¶ 9, 619 P.2d 869.
. King Manufacturing v. Meadows, 2005 OK 78, ¶ 11, 127 P.3d 584; Whitehead v. Independent School Dist. No. 1 of Tulsa County, 2003 OK 26, 18, ¶ 8 P.3d 978, as corrected on denial of rehearing (2003); Beets v. Metropolitan Life Ins. Co., 1999 OK 15, ¶ 6, 995 P.2d 1071, rehearing denied (2000), as corrected (2000); Batt v. Special Indem. Fund, 1993 OK 163, 9, 865 P.2d 1244; Branstetter v. TRW/Reda Pump, 1991 OK 38, 16, 809 P.2d 1305; Knott v. Halliburton, 1988 OK 29, 14, 752 P.2d 812; Weber v. Armco, Inc., 1983 OK 53, 10, 663 P.2d 1221; Lekan v. P & L Fire Protection Co., 1980 OK 56, ¶ 4, 609 P.2d 1289; Lee Way Motor Freight, Inc. v. Wilson, see note 6, infra; Apple v. State Ins. Fund, 1975 OK 88, 1 10, 540 P.2d 545; General Elec. Co. v. Folsom, 1958 OK 279, 18, 332 P.2d 950; Washabaugh v. Bartlett Collins Glass Co., 1936 OK. 294, ¶ 0, 57 P.2d 1162; Pine v. State Indus. Comm'n, 1925 OK 287, 112, 235 P. 617.
. King Manufacturing v. Meadows, see note 4, supra; Beets v. Metropolitan Life Ins. Co., see note 4, supra; Batt v. Special Indem. Fund, see note 4, supra; Branstetter v. TRW/Reda Pump, see note 4, supra; Masoner v. Tosco, 1988 OK 124, ¶ 5, 767 P.2d 410; Bodine v. Crane Carrier, 1988 OK 61, 15, 755 P.2d 675; Weber v. Armco, Inc., see note 4, supra; Lee Way Motor Freight, Inc. v. Wilson, see note 6, infra.
. Special Indemnity Fund v. Weber, 1995 OK 43, ¶ 16, 895 P.2d 292; Lekan v. P & L Fire Protection Co., see note 4, supra; LeeWay Motor Freight, Inc. v. Wilson, 1980 OK 48, ¶ 8, 609 P.2d 777; Apple v. State Ins. Fund, see note 4, supra.
. Batt v. Special Indem. Fund, see note 4, supra; Special Indemnity Fund v. Choate, see note 8, infra; Knott v. Halliburton Services, see note 4, supra; Special Indemnity Fund v. Michaud, 1959 OK 203, ¶ 0, 345 P.2d 891.
. Multiple Injury Trust Fund v. Pullum, 2001 OK 115, ¶ 9, 37 P.3d 899; Samman v. Multiple Injury Trust Fund, 2001 OK 71, ¶ 10, 33 P.3d 302; Autry v. Multiple Injury Trust Fund, 2001 OK 79, ¶ 14, 38 P.3d 213, as corrected (2001), rehearing denied (2001); Batt v. Special Indem. Fund, see note 4, supra; Special Indemnity Fund v. Choate, 1993 OK 15, ¶ 14, 847 P.2d 796; Special Indemnity Fund v. Michaud, see note 7, supra. Special Indem. Fund v. Weber, see note 6, supra, is not to the contrary. In Weber, the Court was not faced with a situation involving vested rights under an employment contract. Rather, the Court's determination that the law in effect at the time of the award would control was based on the fact that the issue presented was a "tax" rather than a condition of employment.
. Title 85 0.$.2001 § 3.6(F), see note 2, supra.
. King Manufacturing v. Meadows, see note 4, supra; Whitehead v. Independent School Dist. No. 1 of Tulsa County, see note 4, supra; Beets v. Metropolitan Life Ins. Co., see note 4, supra; Batt v. Special Indem. Fund, see note 4, supra; Branstetter v. TRW/Reda Pump, see note 4, supra; Knott v. Halliburton, see note 4, supra; Weber v. Armco, Inc., see note 4, supra; Lekan v. P & L Fire Protection Co., see note 4, supra; Lee Way Motor Freight, Inc. v. Wilson, see note 6, supra; Apple v. State Ins. Fund, see note 4, supra; General Elec. Co. v. Folsom, see note 4, supra; Wa-shabaugh v. Bartlett Collins Glass Co., see note 4, supra; M.T. Smith & Sons Drilling Co. v. Breed, 1930 OK 556, 294 P. 137.; Pine v. State Indus. Comm'n, see note 4, supra.
. King Manufacturing v. Meadows, see note 4, supra; Beets v. Metropolitan Life Ins. Co., see note 4, supra; Batt v. Special Indem. Fund, see note 4, supra; Branstetter v. TRW/Reda Pump, see note 4, supra; Masoner v. Tosco, see note 5, supra; Bodine v. Crane Carrier, see note 5, supra; Weber v. Armco, Inc., see note 4, supra; Lee Way Motor Freight, Inc. v. Wilson, see note 6, supra.