(iii) What is the measure of workers compensation paid and payable?
14 The respondent sought to meet the appellant's argument in the following way. First, the respondent did not accept that any payments of workers compensation made in the case were paid in respect of the injury of 4 December 1996. (In the respondent's written submissions, it appeared that it had been accepted by the respondent that he had received compensation payments for the 4 December incident: see para 11 of those submissions. In argument on the appeal, it was said that that was not correct and in effect was withdrawn). Secondly, it was submitted that double compensation in this case was avoided by the operation of s 151Z(1)(b) which imposed an obligation on the respondent to repay the workers compensation insurer out of the judgment sum the total amount of compensation payments made. It followed that the principle in Thackham had no application. Essential to this submission was the respondent's contention that his injuries, disability and incapacity were solely referable to the May injury and, as has already been indicated, that no compensation had been paid or was payable either for the past or for the future in respect of the 4 December 1996 incident.
15 It is convenient at this point to refer to the relevant provisions of s 151Z and to the principle in Thackham. Section 151Z provides, relevantly:
"(1) If the injury for which compensation is payable under this Act was caused under circumstances creating a liability in some person other than the worker's employer to pay damages in respect of the injury, the following provisions have effect:
(a) the worker may take proceedings both against that person to recover damages and against any person liable to pay compensation under this Act for payment of that compensation, but is not entitled to retain both damages and compensation,
(b) if the worker recovers firstly compensation and secondly those damages, the worker is liable to repay out of those damages the amount of compensation which a person has paid in respect of the worker's injury under this Act, and the worker is not entitled to any further compensation,
(c) if the worker firstly recovers those damages the worker is not entitled to recover compensation under this Act
…"
16 Section 151Z deals only with the case where there is a liability in some person other than the employer to pay damages in respect of the injury. Thackham and the cases which followed it deal with a quite different situation, as was explained in Thackham by Handley JA at 506:
"The respondent suffered a work injury on 13 December 1981 while employed by the appellant and a second work injury in March 1988 while employed by Hastings District Hospital. The first gave rise to a cause of action independently of the Act, the second did not, but increased the damages for the first. The question is whether, in terms of s 151Z(1), the second injury 'was caused under circumstances creating a liability in some person other than the worker's (second) employer to pay damages in respect of the injury', that is in the appellant."
17 This question was answered in the negative. Handley JA pointed out that the first injury gave rise to a cause of action independently of the 1987 Act. The second did not, but increased the damages for the first. His Honour further observed that s 151Z failed to expressly make provision for the avoidance of double compensation in cases such as was before the Court. In such cases, it was necessary, as Meagher JA had observed in his judgment at 505, that if over compensation was to be avoided, both compensation paid and payable ought to be deducted. His Honour recognised that would involve a trial within a trial.
18 The operation of the Thackham principle was considered by this Court in Franklins Self Serve Pty Ltd v Wyber (1999) 48 NSWLR 249. In that case Mason P pointed out, at 265, that in Thackham it had been common ground that, if s 151Z did not apply, compensation paid to the worker by the second employer was deductible from the verdict to which the plaintiff was otherwise entitled. Compensation which falls within s 151Z (1) is not deductible but must be repaid by the plaintiff. The monetary result to the plaintiff is the same in each case, but there is a difference in the amount of damages for which the tortfeasor is liable.
19 In the present case if there had been no aggravating incident such as that which occurred on 4 December and the weekly compensation had been paid by the employer's workers compensation insurer as a result of the injuries and incapacity arising from the May accident, the full verdict would have been payable to the respondent by the appellant and the respondent would be obliged, pursuant to the provisions of s 151Z, to repay the compensation amount to the workers compensation insurer.
20 However, there was an aggravating incident which occurred in the course of employment on 4 December. The respondent asserted that this made no difference as the effect of the trial judge's rejection of the application of Thackham and acceptance of Dr Elliott's evidence was that his Honour had determined that all disability and incapacity flowed from the May incident and none flowed from the December incident, so that the December incident did not give rise to an independent right to workers compensation as no incapacity flowed from that injury. He was, however, required to repay the compensation he had received out of the verdict, although he had not done so.
21 The appellant submitted, however, that there was at least some incapacity which flowed from the December incident so that the Court was required to assess what portion of the compensation which had been paid was attributable to that incapacity and what compensation would be payable due to the incapacity flowing from the December incident. It was submitted that his Honour had not undertaken that task. The appellant also sought to demonstrate his point by submitting that, if the respondent's submission was accepted there was nothing to stop him from bringing an application for workers compensation against the employer flowing out of the December incident. This submission elicited a response from the respondent that he had no workers compensation rights in respect of the 4 December incident and would not be making any such claim.
22 At this point a number of things can be noted. First, if the December incident constituted a novus actus, the appellant would not have been liable for any injury or incapacity which flowed from it. His Honour found it was not a novus actus. Secondly, the fact that the December incident did not constitute a novus actus, does not mean that Thackham did not apply. Thirdly, it would seem that his Honour accepted that the December incident caused an aggravation of the May injury. Such an aggravation may still be compensable as part of the damages flowing from the first incident, but that circumstance is also not sufficient to distinguish Thackham: see Wyber at 267. Fourthly, his Honour did not expressly deal with the issue, which is at the heart of Thackham, as to whether the respondent was or would in the future be entitled to the payment of compensation arising out of the December incident. If he was, Thackham applied. Finally, the matter cannot be resolved merely upon the concession made by the respondent that he had no workers compensation rights arising from the December incident: see Thackham, at 509B-C.
23 The undertaking sought to be given in Thackham was that the plaintiff would not pursue compensation rights arising out of the second employment injury. That undertaking was not accepted by the court on the basis that it was not within the court's power to do so. In this case the respondent did not seek to give an undertaking but made a concession that he had no entitlement and would not make any workers compensation in respect of the December incident. It was said that that resolved the matter. Senior counsel for the respondent also argued that, should the respondent commence workers compensation proceedings in respect of the 4 December incident, the concession could be pleaded by the employer as some form of estoppel. The precise nature of such estoppel was not articulated. That is not surprising given that the parties to those proceedings would not be identical to the parties to these proceedings. However, I do not see that the concession made on behalf of the respondent assists in the determination of the issue raised on the appeal. That issue is what deduction, if any, was required to be made from the verdict in respect of compensation paid and payable in respect of the 4 December incident. His Honour did not determine that issue.
24 These matters lead directly to the next point. The only clear finding his Honour made was that he preferred the opinion of Dr Elliott as to the significance of the May 1996 injury, the damage done to the respondent's neck in that injury, and the need for two cervical fusions arising directly out of that injury. Counsel for the respondent sought to deal with the absence of any express finding in relation to his past and future rights to compensation arising out of the December incident by reference to the manner in which the parties had conducted the case at trial. He submitted that the appellant had argued before the trial judge that the respondent's disabilities arose solely from the December incident. The respondent's case was that his injuries and disabilities arose solely from the May incident. It followed, on the respondent's argument, that his Honour's acceptance of Dr Elliott's opinion meant that he accepted the respondent's case in its entirety.
25 I do not agree that the case submitted to his Honour by the appellant was of the categorical nature asserted by the respondent. The matter was put in the alternative - either all disability flowed from the December incident, and if Dr Elliott's opinion was accepted, it did not, in which case Thackham applied: see trial transcript at 277 and 295.
26 In my opinion, as already indicated, the basis of his Honour's decision in finding that Thackham did not apply was erroneous. It was necessary for him to determine whether the December 1996 injury caused any incapacity so as to entitle the appellant to compensation either in the past or in the future.
27 In the normal course, that conclusion would mean that the appellant should have a new trial on this issue. However, I have decided against that course. The effect of Dr Elliott's evidence was that the injury in December 1996 had aggravated the disc prolapse which occurred in the May incident and was only responsible for the subsequent surgery to a minor degree. On that evidence, it would appear that the likelihood of any award arising out of the December incident, either in respect of the period up to the date of trial or beyond would be small.
28 Part 51 r 23 provides relevantly that the Court of Appeal shall not order a new trial unless it appears that some substantial wrong or miscarriage has thereby been occasioned. Accordingly, although I am of the opinion that the appellant has made good his point that the trial judge misunderstood the operation of the principle in Thackham, and did not make the relevant determination required by that principle I would not, in the circumstances, interfere with the trial judge's order. That is so notwithstanding that that leaves the appellant in the position that it is required to pay the full amount of the verdict to the respondent and does not have the benefit of having the verdict reduced as would be the case if there was a finding that there was incapacity flowing from the December incident. As I have said, I consider that any amount so found would have been small and does not warrant the expense of a new trial, even limited to that issue.
29 I would therefore dismiss the appeal from Sorby DCJ with costs.
30 Accordingly, I would propose the following orders: