37 So far as the principle requires that persons be under coordinate liabilities, it has been said that the notion of coordinate liability "defies exclusive or narrow definition" (Mason and Carter, Restitution Law in Australia, para 622). There are established categories, but what underlies the notion is not common liability to be sued but a common risk the burden of which should, if it falls unequally, be adjusted - see Floreani Bros Pty v Woolscourers (SA) Pty Ltd (1976) 13 SASR 313 at 320-1 per Bray CJ -
"The doctrine [of contribution] is an old one. It exists both at law and in equity, though the right in equity is more extensive than the right at common law. It has been variously formulated. It is clear enough from the classic expositions in Dering v Earl of Winchelsea [(1787) 1 Cox 318; 29 ER 1184] and Stirling v Forrester [(1821) 3 Bligh 575; 4 ER 712] that it is not founded on contract but on general principles of equity and justice. I agree with Mr Fisher that it does not depend, in equity at any rate, upon a common liability to be sued. In many of the typical cases, such as the case of goods thrown overboard to save a ship from wreck, or, to take the example in Dering's case [(1787) 1 Cox 318, at p 320; 29 ER 1184, at p 1185], of prisage of wines, when the king had the right in certain cases to take two tons of wine off a ship laden with wine, there was no liability to be sued at all. The various owners of the goods on the ship or of the tons of wine on the ship were merely subject to a common risk of having the goods thrown overboard or taken by the royal prerogative. I think the general principle is stated clearly and explicitly in Rowlatt on Principal and Surety , 3rd ed., p 173, cited by Clauson LJ in Whitham v Bullock [(1939) 2 All ER 310, at 314] as follows:
'If as between several persons or properties all equally liable at law to the same demand, it would be equitable that the burden should fall in a certain way, the court will so far as possible, having regard to the solvency of the different parties, see that, if the burden is placed inequitably by the exercise of the legal right, its incidence should be afterwards readjusted.'
I refer also to the remarks of Vaughan Williams LJ in Bonner v Tottenham & Edmonton Permanent Investment Building Society [(1899) 1 QB 161], a case strongly relied on by Mr Fisher. The learned Lord Justice said at p 176:
'But the plaintiff may be entitled to recover within the equitable principle, if he has been compelled to pay or bear the burden, and can establish that the defendant has such an interest or benefit as to make the maxim apply " Qui sentit commodum, sentire debet et onus " … The equitable principle seems to me based upon natural justice requiring that equity should neutralise " inter se " the accident that the burden had been borne by one for the benefit of others associated with him in interest, whether such incidence of burden is the result of election of a plaintiff who might have sued all those interested, or whether it is the result of the requirements of the law as to the parties to actions, or whether it is the result of what may be more properly called "accident" like the "jettison" of a part of a cargo severally owned, or the seizure of wines on behalf of the Crown in right of prisage. In each of these cases the application of the equitable principle depends on community of interest in something in respect of which one has borne a burden for the benefit of another or others'."
38 Consistently with this, at least in equity contribution as to costs can be obtained. The cases were discussed in Morgan Equipment Company v Rodgers (1993) 32 NSWLR 467, where I concluded that a surety is entitled to contribution from a co-surety for costs reasonably incurred in the successful defence, in whole or in part, of the creditor's claim where that defence would ensure to the benefit of the co-surety. I there said (at 482) -
"It must still be asked upon what principle Wright J acted in Wolmerhausen v Gullick , because the sureties were strictly not under co-ordinate liabilities to pay the costs. The fundamental equitable principle is to achieve equality of burden and benefit, according to the maxim "qui sentit commodum sentire debet et onus": see Dering v Earl of Winchelsea (1787) 1 Cox 318 at 322-323; 29 ER 1184 at 1186; McLean v Discount and Finance Ltd (1939) 64 CLR 312 at 328, 336-337; Albion Insurance Co Ltd v Government Insurance Office (NSW) (at 351-352); Mahoney v McManus (1981) 55 ALJR 673 at 675, 680; 36 ALR 545 at 548-550, 558-560. If all sureties are benefited by discharge of the debt, they should all contribute to the burden. Discharge by successful defence of the creditor's claim on grounds which will enure to the benefit of the co-surety is as much a discharge as payment. It is but a short step to say that costs reasonably incurred in achieving the benefit should form part of the burden, and that a co-surety who has benefited from the discharge of the debt will be required in equity to contribute to the costs.
Consistently with the fundamental equitable principle, therefore, contribution should be available for costs reasonably incurred in the successful defence, in whole or in part, of the creditor's claim where that defence will enure to the benefit of the co-surety. That appears to be what Wright J had in mind when he referred to the plaintiff acting reasonably and in the interests of all parties in resisting and reducing the creditor's claim. To broadly similar effect, although there are some differences in detail, are the statements found in Halsbury's Laws of England , 4th ed, vol 20, para 228, Rowlatt on the Law of Principal and Surety , 4th ed (1982) at 161, Phillips and O'Donovan, The Modern Contract of Guarantee , 2nd ed (1992) at 556 and Goff and Jones, The Law of Restitution , 3rd ed (1986) at 281 (fn 58)."
39 See also Leigh-Mardon Pty Ltd v Wawn (1995) 17 ACSR 741 at 753. In Commercial and General Insurance Co Ltd v Government Insurance Office of New South Wales (1973) 129 CLR 374 there was contribution by a co-insurer to the costs payable to the insured by the insurer found liable, although not to the insurer's own costs (see at 384).
40 Returning to s 5 of the 1946 Act, the tort feasor found liable and the contributing tort feasor are under coordinate liabilities to make good the one loss as to damages. The 1946 Act reinstated the principle of natural justice by abolishing the rule in Merryweather v Nixan, and went further by specifically providing for unequal contribution between the tort feasors. The tort feasor found liable and the contributing tort feasor are in one sense not under coordinate liabilities to make good the one loss as to costs, because the order in favour of the plaintiff is only made against the tort feasor found liable. But if there is to be complete recognition of the principle of natural justice, and equality of benefit and burden, costs should be treated in the same way as damages. The plaintiff could have sued either the tort feasor found liable or the contributing tort feasor, or both. Recovery from the tort feasor found liable will discharge the contributing tort feasor. If the plaintiff had sued the contributing tort feasor instead of, or as well as, the tort feasor found liable, the contributing tort feasor would have been ordered to pay the costs. So it is just and equitable that the burden of the plaintiff's costs should be shared between the tort feasors, so that the burden will not fall on one of them to the exclusion of the other because the plaintiff chose to sue only the one.
41 This presupposes that the litigation would have proceeded in the same way, with the same costs incurred by the plaintiff if the plaintiff had sued the contributing tort feasor instead of the contributing tort feasor. The effect of s 5(2) is that the contribution as to costs is by the same measure as the contribution as to damages, that which is just and equitable having regard to the extent of the contributing tort feasor's responsibility for the damage. There is no room to adjust the contribution as to costs if it be thought the tort feasor's conduct of the litigation unreasonably increased the plaintiff's costs. But self-interest is a powerful influence on conduct, and mis-management is not to be assumed. The tort feasor's own interests call for minimisation of the plaintiff's costs, and I do not see this as sufficient reason to conclude that the contribution does not extend to contribution as to costs.
42 The wording of s 5 permits the contribution to extend to contribution as to costs, and construing it as extending to costs gives effect to fundamental principle. It is perhaps not surprising that, as Handley JA's reasons record, Professor Williams said without discussion that contribution could be ordered towards costs payable to the injured party (para 15), and that many instances of such orders are to be found (paras 14, 16). To the instances cited by his Honour may be added cases in Ontario on a similar, but not identical, statute, see Catt v Coveyduck [1950] OWN 176; Colonial Coach Lines Ltd v Bennett (1967) 66 DLR (2d) 396; and Stewart v London Transport Commission (1968) 1 DLR (3d) 550.
43 In my opinion, there was power under the 1946 Act to order that the Council contribute to the costs payable by the company to the plaintiff. Contribution to the tort feasor's own costs is another matter, as to which I say nothing.
44 Since the measure of the contribution is found in s 5(2), the question of the power under s 29 of the Dust Diseases Tribunal Act does not arise, nor does the question concerning discretion. As I earlier indicated, those questions fall away upon resolution of the first question.
45 To repeat, I agree with the orders proposed by Handley JA.
46 HEYDON JA: I agree with Giles JA and, subject to the qualifications advanced by Giles JA in relation to Handley JA's reasoning, with Handley JA.
47 Some judicial support for the correctness of the conclusions they have reached is to be found in Smith v Bray (Wickham, Third Party) (1939) 56 TLR 200. After Hilbery J found for the plaintiff in a negligence action, and awarded her £185 damages, he found that a third party joined by the defendant "should pay half the damages". Counsel for the defendant "asked that the contribution should extend to the costs payable by the defendant to the plaintiff." At 201 Hilbery J is reported as saying: "Is that within the Act?" The report continues as follows:
"[Counsel] submitted that it was. It had certainly been done in many cases, and he understood that the usual form of order had been drawn up by four of the Judges. He submitted that 'responsibility for the damage' [in the then English equivalent to
s 5(2)] meant 'for the whole liability of the tortfeasor', not only 'for damages awarded by the Court'."
48 Hilbery J then said:
"Very well. I am satisfied for the moment that I have power to order the third party to contribute part of the costs recoverable from the defendant. But the third party appears in person and is not able to argue this question of construction of the Act, so I reserve the right to alter this view in the future if the point is fully argued. There will be judgment for the plaintiff for £185 and costs against the defendant, and for the defendant against the third party for half those damages and half those costs, with such costs as are attributable to the third-party proceedings."