Why apply foreign law?
Why should a court apply foreign law? It might be imagined that everything could be satisfactorily decided under its own law. A moment's thought, however, reveals that there are at least some situations in which foreign law has to be applied. Take the case of two people, a man and a woman, who have lived all their lives in country X. They are citizens of that country and are domiciled there. They marry there, taking care to ensure that they comply with the requirements of the local law. If, many years later, they go to country Y on a visit, it would be monstrous if their marriage was not recognized because they had not complied with the formalities laid down by the law of country Y.
Marriage is a status, but it is not only in this case that foreign law has to be applied. Think of a testator who makes his will according to what appears to be the only relevant law. It would again be monstrous if a foreign country refused to recognize the will because it did not comply with its own law. Or take the case of a person who ensures that his actions are lawful under what appears to be the only relevant law. Would it be right if a court in another country held that he had committed a tort because what he did would have been a tort under its law?
One can generalize from these examples by saying that, if a person tailors his actions to comply with what appears to be the relevant law, a foreign court ought not to upset his expectations by refusing to apply that law. One can in fact go further and say that a court ought to be willing to apply foreign law whenever this is necessary to uphold the reasonable expectations of the parties, even if there is no evidence that either of them made a special effort to comply with that law.
Upholding expectations is one of the main policy objectives of choice of law. However, it is not the only one. There might also be public purposes that require foreign law to be applied.