This is a petition to review an award of the Industrial Accident Commission. The cause was before the District Court of Appeal, Fourth Appellate District, and an opinion was rendered therein by Mr. Justice pro tern. Harden, which we incorporate in part as a correct presentation of the facts and a proper determination of certain issues. The portions of said opinion which we incorporate are as follows:

' Petitioner also makes the point that the Commission erred in allowing certain charges made for medical care and treatment. We are satisfied, from a careful study of the record, that the evidence before the Commission was sufficient to justify its determination in this regard, and that no useful purpose would be served by a detailed enumeration of the items and the supporting evidence.

The important question in this appeal, for the consideration of which this court ordered a hearing, is whether the Commission should have granted to petitioner, the employer, a credit for a portion of the amount received by settlement with the third party. It appears that in making the settlement, the parties had in mind the sum of $2,500 as compensation for the injury, and $1,000 for pain and suffering. Since the elements of pain and suffering are not compensable by the Commission (see Jacobsen v. Industrial Acc. Com., 212 Cal. 440 [ 299 Pac. 66 ]), the county makes no claim for credit as to that sum which represents these elements, but does seek a credit in the sum of $2,500, on its liability for compensation under the Workmen’s Compensation Act.

Prior to the decisions of this court in Jacobsen v. Industrial Acc. Com., supra, and Zurich Gen. Acc. etc. Ins. Co. v. Industrial Acc. Com., 212 Cal. 451 [ 299 Pac. 70 ], the Commission had established the practice of granting credit to the employer on his liability for compensation, for the purpose of avoiding a double recovery by the employee. In the Jacobsen ease we held that this practice was unauthorized by the statute, which gave the employer the remedy of asserting a lien in any action brought by the employee against the third party. We held also that failure to assert the lien in that manner was a waiver thereof, and that the Commission had no power to take care of this omission by a mere rule of practice. It will be observed that the Jacobsen case differs from the instant case in two important particulars. First, in the instant case there was no action brought by the employee; a private settlement was effected by her. Hence there was no opportunity for the employer to assert a lien as provided by the statute. Second, the employee made the settlement without notice to the employer, in violation of the express terms of the statute, and hence the employer was not in a position to assert and protect its rights. That these distinctions are of importance is indicated by the language of the Zurich Gen. Acc. etc. Ins. Co. case, supra, as follows: “From what has been said in the Jacobsen case and in this opinion, it should be understood that the problem presented and determined applies only to cases where the employee recovers a judgment against a third party tortfeasor in an action for damages for the negligence of the latter. The power of the Commission otherwise to order credits and liens under the act is not affected.” ( 212 Cal. 453 [ 299 Pac. 71 ].) There is nothing in these decisions which denies to the Commission the power to grant a credit in cases where no action is brought by the employee, and no waiver of the employer’s lien may be implied.

It is suggested, however, that since the employee entered into the settlement without notice to the employer and consequently in violation of the act, the settlement agreement was void, and the employer could claim no credit based upon receipt by the employee of money under such settlement. The implications of such a conclusion are somewhat start ling. On its face it results in a double recovery by the employee as a reward for her own violation of the law. In theory, of course, the employer could sue the third party for reimbursement of its expenditures for compensation, provided that the statute of limitations had not already run; as a practical matter, it would seem that the statute has already barred this right of action. However, the statute may not, perhaps, have run upon the right of the third party to recover money paid to the employee under a void contract, in which case the responsible third party might be wholly absolved, and the innocent employer held responsible for full compensation, and all because of the wrongful act of the employee. The absurdity of this result both on the merits and because of the multiplicity of suits which it engenders indicates the unsoundness of the view contended for. In our opinion, the provision of the statute requiring notice to the employer is intended solely for his benefit, and a violation thereof should, no doubt, render the settlement voidable at his election, but certainly not void where the result would be injurious to his interests. It should not be possible for the employee, having received the benefits of the settlement, thereafter to assert its invalidity in order to reap a further profit. The settlement must, ive think, be considered valid as against the employee because the employer does not attack its validity, and the employee has received a benefit therefrom.

No positive statutory provision operates, as it did in the Jacobsen case, to prevent the granting of a credit in this proceeding. The evidence of segregation made by the parties of the sums received in settlement was sufficiently clear and definite for the Commission to determine that $1,000 thereof was allocated to pain and suffering, and that this item should not be included in the credit. It would seem, therefore, that the Commission, in order to prevent a gross perversion of the purpose of the statute, should grant the requested credit.

We reach this same conclusion on another ground. In 1931, following the decision in the Jacobsen case, the legislature amended section 26 of the Workmen’s Compensation Act to provide expressly for the power denied in that case. The relevant provision now reads: 1 ‘ The Commission is empowered to and shall allow a credit to the employer to be applied against Ms liability for compensation the amount of any recovery by the employee for his injury, either by settlement or after judgment, that has not theretofore been applied to reimburse the employer.” While the injury to Mrs. Allen was sustained prior to the enactment of this amendment, the decision and award of the Commission, which are here attacked, were made after the amendment went into effect. How, then, could the Commission disregard it in arriving at its determination? As a matter of interpretation, the amendment in its language plainly applies to any case before the Commission at the time of its effective operation. There is nothing in its wording to suggest that it was not intended to apply to cases where the injury occurred prior thereto. Nor is there any policy opposed to such application. The amendment was designed to permit the Commission to do what the court theretofore alone could do—prevent double recovery by crediting the employer with the employee’s recovery against the third party. Its application in the instant case would avoid a multiplicity of actions and the unfair result already discussed.

The same factors determine the question of constitutionality. Assuming that the statute, as above interpreted, may be called a retrospective law because it applies to a situation which took place before its enactment, this by no means leads to the conclusion that its application violates the Constitution. Invalid retrospective legislation falls into three classes: esc post facto laws, or retrospective criminal statutes; laws impairing the obligation of contract; and laws which deprive a person of a vested right. (See Los Angeles v. Oliver, 102 Cal. App. 299 [ 283 Pac. 298 ].) It is obvious that no contract obligation would be impaired by the construction herein placed upon the statute, and the only remaining question is whether a vested right has been curtailed or destroyed, in violation of the constitutional guarantee of due process of law. Here it is also obvious that the constitutional inhibition does not apply, for the amendment to the statute applies solely to procedure, and does not affect the substantive rights of the employee. As already pointed out, the employee has no right, under the statute, to a double recovery for the injury; and the statute in force at the time of the injury gave the employer the right to obtain, and the court the power to grant, a lien upon the judgment in reimbursement of expenditures for compensation. This lien, in purpose and effect, is the exact equivalent of the credit which is now granted by the Commission. The change is simply in the manner in which and the body by which it is granted. Nothing to which the employee was formerly entitled has been taken away. A limitation upon his rights which formerly existed is simply made easier to apply, in the same proceeding in which compensation is sought, instead of solely in a court in which an action may be brought.

In Los Angeles v. Oliver, supra, numerous cases were reviewed, and the governing principle was correctly stated, as follows ( 102 Cal. App. 315 ) : “It is a well-settled rule of law that the legislature may change rules of procedure, or remedies, and that such changes may be made applicable to pending actions, provided, of course, that under the guise of a mere change of procedure or substitution of remedies vested rights are not destroyed or the obligation of contracts impaired (Buck v. Canty, 162 Cal. 226 [ 121 Pac. 924 ] ; Aikins v. Kingsbury, 170 Cal. 674 [ 151 Pac. 145 ]; Bassford v. Earl, 172 Cal. 653 [ 158 Pac. 124 ]); and so long as a reasonably efficient remedy remains (Kerckhoff-Cuzner Mill & Lumber Co. v. Olmstead, 85 Cal. 80 [ 24 Pac. 648 ] ; Lantz v. Fishburn, 17 Cal. App. 583 [ 120 Pac. 1068 ]). As said by Judge Cooley in his work on Constitutional Limitations, ‘the bringing of suit vests in a party no right to a particular decision.’ (Cooley’s Constitutional Limitations, 8th ed., p. 789.) When a law only affects the remedy or procedure, ‘all rights of action will be enforceable under the new procedure, without regard to whether they accrued before or after such change in the law and without regard to whether the suit had been instituted or not, unless there is a saving clause as to existing litigation.’ (People ex rel. Foote v. Clark, 283 Ill. 221 [ 119 N. E. 329 ].)”

The above-quoted opinion, which dealt with the application of a statutory change to pending proceedings in eminent domain, contains other language which seems peculiarly applicable here. Quoting first from Pacific Gas & Electric Co. v. Chubb, 24 Cal. App. 265 [ 141 Pac. 36 ], it is said: “ . . . the procedure by which this just compensation is to be ascertained is as much the subject of statutory law as is the procedure hy which the property is to be taken. There is no way to exercise the right of eminent domain except as prescribed by statute, and there is no way for the property owner to secure just compensation for his property except by statute law.” The court in the Oliver case continues: “It would thus appear that the procedure by which the amount of compensation is to be ascertained and determined is not within, or a portion of, the right guaranteed by the Constitution and therefore vested in the property owner.”

Other illustrations of this principle may be easily found. Thus, in City of Chicago v. Industrial Commission, 292 Ill. 409 [ 127 N. E. 46 ], an amendment to the Workmen’s Compensation Law, limiting the time within which a writ of error to review the cause might be obtained, was applied to a case where proceedings for compensation were instituted prior to the amendment. In Rice v. Dunlap, 205 Cal. 133 [ 270 Pac. 196 ], this court held that a change in section 438 of the Code of Civil Procedure, enlarging the scope of counterclaim by a defendant, would be applicable to a new trial after a reversal, even though the plaintiff’s cause of action accrued and the original action was filed before the amendment. We there said ( 205 Cal. 137 [ 270 Pac. 198 ]) : “ . . . the defendant . . . will be entitled to the benefit of any changes in the adjective or procedural law which have been made by the legislature up to the time of the new trial.” In Maguire v. Cunningham, 64 Cal. App. 536 [ 222 Pac. 838 ], it was held that the amendment of 1921 to section 738 of the Code of Civil Procedure, giving the remedy of quiet title in actions concerning personal property, was to be retroactively applied to a pending action. (See generally, note, 35 Harv. L. Rev. 193 .)

The conclusion necessarily follows that the Commission erred in refusing to credit the employer on its liability for compensation, in the amount claimed. It is therefore ordered that the award be annulled, and the cause is remanded for further proceedings not inconsistent with this opinion.

Mr. Justice Curtis, deeming himself disqualified, did not participate in the foregoing opinion.