Can a third party claim credit for the amount of workmen's compensation awarded to a plaintiff as a result of negligence?

Obviously, in a case where the employer's concurrent negligence is a potential but unasserted issue, neither the employer nor his insurer will be likely to join in the suit voluntarily. Equally obvious is the disinterest of plaintiff who has no financial stake in the presence or absence of these parties. He cannot enjoy a double payment by retaining the workmen's compensation payments on top of his damages. (Witt v. Jackson, supra, 57 A.C. at pp. 73-74, 17 Cal.Rptr. 369, 366 P.2d 641.) If the employer was negligent the third party gets credit for the workmen's compensation benefits. If the employer was not negligent his insurer recovers them as a result of his lien. The defendant third party, therefore, does have a vital interest in having the issue determined; because his monetary liability will be reduced by the amount of said benefit payments upon proof of the employer's concurrent contributing negligence.