(B) THE GROUNDS OF RESTITUTION ARE NOT CLOSED
In CTN Cash and Carry Ltd v Gallaher Ltd41 Sir Donald Nicholls V-C recognized that the grounds of restitution are not closed. This is exemplified by the explicit judicial creation of two grounds of restitution, namely the recovery of ultra vires payments from public authorities42 and absence of basis.43 There is nothing to stop new grounds of restitution being recognized in the future, but it is vital that the existence and definition of such grounds can be justified by reference to at least one of the three underlying rationales which justify the recognition of grounds of restitution.
(C) THE RELEVANCE OF THE TYPE OF ENRICHMENT
One issue which has proved to be particularly controversial is whether each ground of restitution should be applicable regardless of the type of enrichment which is involved, or whether certain grounds of restitution are only applicable to particular types of enrichment. This issue has proved to be particularly significant in respect of restitutionary claims which are founded on failure of basis,44 where traditionally the ground has only been applicable in respect of claims to recover money. The issue is also significant in respect of claims grounded on mistake.
Whilst every ground of restitution clearly applies to money claims, there has been some doubt whether every ground of restitution can apply where the claimant seeks restitution of a non-money benefit. This is largely because judicial analysis of restitutionary claims in respect of non-money benefits has been restricted by excessive reliance on the old forms of action. Typically, the decision to award restitutionary remedies is expressed simply in terms of granting a quantum valebat for goods or a quantum meruit for services.[1] The incantation of these Latin phrases avoids the need for rigorous legal analysis. But it is not acceptable for a principled law of restitution to rely on such an approach. It is vital to identify the ground of restitution involved, since the simple fact that the defendant has received a non-money benefit from the claimant does not in itself provide any reason why the restitutionary claim should or should not succeed.
There is no reason why the application of any of the grounds of restitution should depend on the nature of the enrichment which the defendant has received.[2] In fact, careful analysis of those cases where a quantum valebat or quantum meruit was awarded suggests that the court could have awarded the claimant a restitutionary remedy by reference to one of the recognized grounds of restitution, such as mistake[3] [4] or failure of basis. Indeed, the House of Lords in Yeoman’s Row v Cobbe48 has unequivocally recognized that a restitutionary claim for services can be grounded on failure of basis. There is no reason now to think that the application of any of the grounds of restitution depends on the nature of the enrichment.
