As a general principle, a will, once made, can be revoked or changed providing that the person making the will is mentally capable and that certain formalities are followed.

However, there are some exceptions to this principle and one of them can be clearly demonstrated by the story of Geoffrey Gillett and Kenneth Holt.

Mr. Holt was a Lincolnshire farmer and a bachelor of considerable means. Mr. Gillett was a police officer's son and a grammar school boy who in his teenage years earned a little pocket money as a caddie on a golf course.

He was 12 in 1952 when he met Mr. Holt and became his regular caddie. In due course, he began to help out on Mr. Holt's farm and when he was 15, he left school and began to work full time for Mr. Holt.

Mr. Holt treated Mr. Gillett like a son. He gave him increasing responsibility in the farming enterprise and they enjoyed many sporting activities together.

Mr. Gillett lived on the farm with Mr. Holt where a housekeeper looked after the two men.

By the time Mr. Gillett was 24, Mr. Holt trusted him sufficiently to leave him in Lincolnshire in charge of the harvest while Mr. Holt went off to fish in Iceland.

Around the time of the 1964 harvest, Mr. Gillett recalled that Mr. Holt took he and his fiancée out for dinner.

This dinner was significant since it was the first occasion on which Mr. Holt stated to Mr. Gillett that upon Mr. Holt's death, he would inherit the farm.

In the subsequent court case, Mr. Gillett gave evidence that on six further occasions Mr. Holt promised him that he would receive a significant inheritance.

On one occasion Mr. Holt showed Mr. Gillett a document that he understood to be a will while on another Mr. Holt is reported to have told Mr. Gillett "it is all yours".

As things turned out, however, it was not "all his" and by 1995, Mr. Gillett and Mr. Holt had fallen out.

Mr. Holt changed his will on a number of occasions and ultimately excluded Mr. Gillett from it. Mr. Gillett then pursued a court case seeking to claim that Mr. Holt was bound to make good his assurances that he would inherit.

Mr. Gillett was ultimately successful in the Court of Appeal in England in a case that has been referred to by the Supreme Court of Bermuda.

Mr. Holt's will was upset by what is known as the doctrine of "proprietary estoppel". There are three central aspects of this doctrine. There must be an assurance or promise, the party claiming must have relied on the assurance or promise, and the party claiming must have acted to his or her detriment in reliance on the assurance or promise.

The theory behind this doctrine is that the courts will step in to prevent unconscionable conduct. Mr. Gillett was able to prove that Mr. Holt had repeatedly made assurances to him that he would inherit the farming business.

It was also accepted by the Court of Appeal that Mr. Gillett had relied on Mr. Holt's assurances to his detriment.

While Mr. Gillett was paid throughout his years of work for Mr. Holt and had acquired other benefits, the Court of Appeal decided that the issue of "detriment" should be viewed "in the round".

The Court found that Mr. Gillett had made sacrifices for Mr. Holt and had devoted the best years of his life to working for him. He had, for example, left school early without qualifications when he could easily have completed his education.

The Court found that he had showed loyalty and devotion to Mr. Holt's business interests and personal wishes all on the strength of clear and repeated assurances that he would inherit.

In the circumstances, the Court of Appeal found that Mr. Holt should not be allowed to go back on his assurances. The story does not end there, though, since depending on the facts of each case the courts may not enforce the assurance or promise in full.

Much depends on the nature and duration of the assurances and the extent of the detriment.

If a proprietary estoppel claim is made out the court will consider what form of compensation is appropriate to do justice between the parties.

Sometimes the result is an order for the transfer of land or some lesser interest in land. In other cases, the compensation ordered will be the payment of money. The end of Mr. Gillett's story is that he did not receive the whole of Mr. Holt's substantial farming enterprise.

Rather, the Court of Appeal decided that, taking into account the benefits that he had received over the years, he should receive a farmhouse, about 100 acres of land and a modest sum of money.

The Court decided that this was appropriate compensation for what the Judge called his "exceptionally long and devoted service".

Attorney Keith Robinson is a member of the Litigation and Insolvency Practice Group at Appleby. A copy of Mr. Robinson's column can be obtained on the Appleby website at www.applebyglobal.com. This column should not be used as a substitute for professional legal advice. Before proceeding with any matters discussed here, persons are advised to consult with a lawyer.