(B) THE CONSEQUENCE OF THE CLAIMANT BEING ESTOPPED
The effect of successfully pleading estoppel is that usually the restitutionary claim is barred completely, even though the defendant may not have spent all of the money which was [1] [2] [3] [4] [5] [6]
received. In other words the defence does not operate pro tanto,39 unlike the defence of change of position.[7] [8] The effect of this is illustrated by Avon County Council v Howlett41 where the claim to recover ?1,007, which the claimant had mistakenly paid to the defendant, was defeated even though the defendant had pleaded that he had only changed his position to the extent of ?546. Estoppel is considered to operate as a complete defence to the restitutionary claim simply because it is an evidentiary rule which prevents the claimant from adducing facts which contradict the representation on which the defendant has detrimentally relied.[9] [10] Whilst this obviously makes the defence more attractive to defendants, it is liable to produce unjust results, for if the defendant has been unjustly enriched by the receipt of ?1,000 and, in reliance on the claimant’s representation, parts with ?200, he or she remains unjustly enriched to the extent of ?800. The potential injustice arising from the operation of the defence was recognized by the judges in Avon County Council v Howlett,43 particularly where the defendant’s change of position is small in comparison with the value of the enrichment which he or she had received. There are a number of ways of avoiding this extreme result.
- [1] [1923] 1 KB 504. 32 (1895) 73 LTR (ns) 669. 33 [1983] 1 WLR 605.
- [2] 34 Ibid, 621 (Slade LJ). 35 [1933] AC 51. 36 [1976] 1 WLR 964, 968.
- [3] 37 [1949] 2 KB 683. This qualification was also recognized by Slade LJ in Avon CC v Howlett [1983] 1 WLR
- [4] 605, 621.
- [5] 38 George Whitechurch Ltd v Cavanagh [1902] AC 117, 145 (Lord Brampton); National Westminster Bank
- [6] Ltd v Barclays Bank International Ltd [1975] QB 654, 676 (Kerr J).
- [7] This was affirmed by Lord Goff in Lipkin Gorman (a firm) v Karpnale Ltd [1991] 2 AC 548, 579. See alsoAvon County Council v Howlett [1983] 1 WLR 605,622 (Slade LJ) and Greenwood v Martins Bank Ltd [1932] 1KB 371 (CA), affirmed [1933] AC 51 (HL).
- [8] See p 678, below. 8 [1983] 1 WLR 605 . 3 Ibid, 622 (Slade LJ).
- [9] 44 AS Burrows, The Law of Restitution (3rd edn, Oxford: Oxford University Press, 2011), 555.
- [10] 45 Note the similar approach in respect of the ground of restitution of total failure of basis where it is
