Professor Birks (in response to a critique by Professor Burrows) has stressed that 'free acceptance' should not be understood as meaning that the recipient values the thing in question, but as unconscientious conduct precluding him or her from exercising the usual right to assert that he or she was not subjectively benefited: see In Defence of Free Acceptance in Essays on the Law of Restitution (ed.

Citing some extreme examples (holding a pistol to a doctor's head and demanding medical treatment, stealing goods and intentionally using another's land without permission), he goes on: "Although there are no authorities specifically on this point, the defendant in such situations must be regarded as benefited (by the objective value of the subject matter).

He cannot rationally say that he was indifferent to receiving the thing: and he cannot be allowed to raise the argument 'I was not willing to pay' because his reprehensible conduct shows a disregard for the bargaining process (ie the market system).

But as the argument for this test is one of principle, without direct support from the case law, it has been considered preferable to focus on the stronger case whether the conduct is also reprehensible"It is of interest to recall that Professor Birks' explanation of the theory of 'free acceptance' is that the recipient's 'unconscientious conduct' precludes him or her from denying subjective benefit.

Notes B, C and E to the form Retention of Vehicle Registration Number V778/1 (trial document E14) indicate that Mr McDonald could, even on 13th December 2000, have applied to retain the mark, with a view to re-transferring it to the estate or its order.

Only on or about 10th January 2001 did the DVLA register him as the keeper of the car with the mark TAC 1, so that he had every opportunity to correct the position before the mistake made in his favour was consolidated.

Bearing in mind the circumstances in which Mr McDonald came to register in his name a car carrying the mark TAC 1, it could, I think, be regarded as falling within the general principle of free acceptance advocated by Professor Birks and Goff & Jones.

On and after 13th December 2000 Mr McDonald was acting unconscientiously in seeking and in insisting upon such registration, in the knowledge that this was not in accordance with the bargain made and that there had been an obvious mistake.

But it is designed to overcome any suggestion of indifference, and it could be consistent with this rationale if the test were, if necessary, given a slightly wider re-formulation to cover circumstances such as the present.

The qualification "reprehensible" derives from what Professor Burrows himself describes as "the stronger case" where the defendant shows a 'disregard for the bargaining process".

What happened involved sufficient elements of knowledge, choice and action to overcome any suggestion of indifference, and can once again be seen as reprehensible in so far as it was in conscious disregard of the prior bargain.

This basis of recovery was approved in principle by Hirst J in a dictum in Procter & Gamble Philippine Manufacturing Corpn.

2) [1979] 1 WLR 783, Robert Goff J used a similar phrase at p.805D in relation to the Law Reform (Frustrated Contracts) Act 1943, which he explained at p.799D as grounded on principles of unjust enrichment.

Goff & Jones recognise that not every financial gain may be said to be realisable, and refer in this connection to the landowner who "subject to the equitable doctrine of acquiescence, is not obliged to make restitution to the mistaken improver even though the land can of course be sold or mortgaged".

In The Manila Hirst J recorded that it had been common ground between the parties that the test in cases of receipt of services was appropriately set out in Goff & Jones as being whether the defendant had "gained a financial benefit readily realisable without detriment to himself" (p.855f).

In Marston Construction Co. Ltd. v. Kigass Ltd. (1989) 46 BLR 109, HHJ Bowsher QC preferred Goff & Jones's to Professor Birks' approach.

Goff and Jones' view avoids this problem but has its own weakness because what is realisable cannot depend just on whether it is land or a chattel that is improved.

If the test suggested by Goff & Jones were accepted, there would of course be no difficulty in concluding that Mr McDonald received a readily realisable benefit.

Professor Burrows' modified approach, requiring us to consider whether it was also reasonably certain that Mr McDonald would realise the financial benefit, would seem difficult to apply in or adapt to the present situation.

Even if one were to attempt to ignore the gift away, it would be difficult, if not impossible, to consider what a defendant's intention would have been regarding realisation, if he had not given the benefit away, when giving it away is what he actually chose to do.

The mark is not a chattel, and it was not suggested before us that its return could at any stage (even before the gift to the partner) have been enforced, or that its non-return could sound in damages.

However, Mr McDonald's insistence on keeping the mark and the absence of any obvious means of compelling its re-transfer are reasons for analysing this case in terms of unjust enrichment.

Mr McDonald's responses under cross-examination were to the general effect that the registration mark was a matter of indifference to him and to his partner (cf transcript pp.9-10 and judgment p.11F).

The inference is that Mr McDonald, despite his denials, attached real value to the mark, and determined that it should be retained for that reason.

In these circumstances, and in agreement with the judge, I would conclude that Mr McDonald received an incontrovertible benefit in the market value of the mark.

Viewing the matter in the terms in which counsel presented it, there could be no difficulty in reaching this conclusion on the simple test of realisability advocated by Goff & Jones.

In my view, however, the law must in any event recognise as a distinct category of enrichment cases of readily returnable benefit, of which the present is an example.

By the time Mr McDonald gave the car away, he knew that there had been a mistaken failure to obtain any right of retention under the statutory scheme and that both the estate and Coys would be pursuing him to recover the mark or its value.