(C) PLACE WITHIN THE LAW OF UNJUST ENRICHMENT

The problem with the action for reimbursement in circumstances of necessity where there is a pre-existing legal relationship between the parties is whether it really forms part of the law of unjust enrichment. The difficulty arises from the requirement that there must be a pre-existing relationship, whether it be agency or bailment or whatever. The effect of the doctrine is that the claimant’s authority under this relationship is extended to include the reaction to the emergency.^[1] This suggests that this doctrine is part of the law governing the pre-existing relationship, such as contract, rather than the law of unjust enrichment, with the consequence that, if the claimant has a remedy, it will be contractual rather than restitutionary. Whilst this may be true in most cases, there is still a role for the doctrine to apply within the law of unjust enrichment, as was recognized by the Supreme Court in The Kos,^[2] although this role is likely to be very limited, if it actually exists at all. In that case the claimant, the owner of a ship, brought proceedings against the defendant charterers for expenses incurred in caring for the defendant’s cargo whilst it was on board the claimant’s ship. The cargo had been bailed to the claimant under a contract which had come to an end whilst the cargo was still in their possession. On the facts of the case a contractual claim for reimbursement succeeded, but the Supreme Court also considered that the claimant could recover as a non-contractual bailee. This was because, since the bailment was originally under a contract which had terminated, the claimant had no choice but to remain in possession of the cargo. It had a continuing duty as a non-contractual bailee to take reasonable care of the cargo and this duty provided the basis for imposing an obligation on the charterers to pay for the cost of that care. The decisions in Great Northern Railway v Swaffield^[3] and The Winson^[4] were analysed in the same way. It follows that the liability arises from the law of bailment, which is an independent source of rights and obligations,^[5] rather than the distinct doctrine of agency of necessity and also the law of unjust enrichment. But it does not follow that there is no scope for an unjust enrichment claim in such cases, since this was expressly acknowledged by Lord Sump- tion,^[6] who considered that the measure of recovery might be different, although he did not explain how. Lord Mance considered that the bailee could recover for their time and expense in looking after the cargo.^[7] He also considered that the bailor might be subject to a restitutionary liability ‘in respect of any benefit they could be said to have had through the storage on board the vessel of the cargo’. But since this benefit must have been obtained at the expense of the claimant bailor, it is difficult to see how this would be different from the bailor’s time and expense in looking after the cargo.

This suggestion that the bailor would have an alternative claim in unjust enrichment, albeit with the same measure of recovery as under the law of bailment, does cause significant doctrinal difficulties since, where the duty arises under bailment, this is a legally effective basis for liability,^[8] which should mean that there is no scope for an independent claim in unjust enrichment. Similarly, where there is agency of necessity, the principal will be liable to pay the claimant under the law of agency, which again constitutes a legally effective basis, thus excluding a claim in unjust enrichment. It is only where there is no genuine agency relationship and no bailment that there can be any legitimate scope for a claim in unjust enrichment where there is a pre-existing relationship between the parties. Since agency and bailment are likely to cover most, if not all, of the cases where there is a pre-existing relationship between the parties, it follows there is likely to be little scope for an unjust enrichment claim in such circumstances.

• [1] De Bussche v Alt (1878) 8 Ch D 286, 310.
• [2] ENE Kos 1 Ltd v Petroleo Brasileiro SA (No 2) [2012] UKSC 17, [2012] 2 AC 164.
• [3] See p 302, above. 98 See p 303, above.
• [4] 99 Yearworth v North Bristol NHS Trust [2009] EWCA Civ 37, [2010] QB 1, 22 (Lord Judge CJ).
• [5] 100 ENE Kos 1 Ltd v Petroleo Brasileiro SA (No 2) [2012] UKSC 17, [2012] 2 AC 164, [31].
• [6] 101 Ibid, [55]. 102 See p 133, above.
• [7] 103 For detailed examination of salvage see FD Rose (ed), Kennedy and Rose on The Law ofSalvage (8th edn,
• [8] London: Sweet and Maxwell, 2013).