ABSTRACT
A claim in unjust enrichment operates on the following, very simple basis. A claimant may bring an action for unjust enrichment where the defendant has been ‘enriched’ as a result of some ‘unjust factor’ at the claimant’s expense. The unjust factors are presented differently in Birks and Chambers’ Restitution Research Resource and in the many other publications, the contents of which are hotly debated among the restitution academics. They include well-known actions such as mistake, undue influence, duress and so forth, which are said to trigger a claim for unjust enrichment. The responses which the law should give are also listed. By way of illustration, it is said that a resulting trust could be understood as identifying an enrichment in the defendant’s hands in the form of an item of property which, for example, the defendant had acquired by mistake, and then pulling that property (that is, the enrichment) back into the claimant’s hands. However, this model of the resulting trust was rejected by the House of Lords in Westdeutsche Landesbank v Islington LBC.1 The law on tracing, resulting trust, subrogation and so forth has been analysed through this lens, as discussed in earlier chapters. The question is whether unjust enrichment thinking offers any better answers to these questions than does equity at present.
