To plead the Statute of Frauds in an action for non-delivery or non-acceptance of goods under such informal agreements might be a defence in the law courts, but would not save the defendant from the indeterminate but effective penalties due to the feeling of his fellows that he was acting dishonourably.

It is instructive to notice that in dealing with the question of industrial disputes, which are in many ways analogous to international, at least where they arise between organised bodies of employers and of workpeople, the Whitley Committee, in a supplemental report issued in January, 1918, expressed the opinion: (1) that no attempt should be made to establish compulsory arbitration or compulsory legislation to prevent strikes and lock-outs; (2) that there should be standing arbitration councils or panels of arbitrators to whom disputes arising could be voluntarily referred; (3) that provision should be made for independent inquiry and report as to the merits of trade disputes; (4) that legal penalties for breach of an award or of an agreement made to settle a trade dispute should not be imposed; (5) that the decisions of industrial tribunals and arbitrators should be co-ordinated as far as possible, and that there should be opportunity for interchange of opinion between the arbitrators whose awards should be circulated.

A body of customary law on the subject would thus grow up without legal sanction, but of great value in promoting uniformity and preventing the ill-feeling which would arise from conflicting decisions in different cases involving similar questions.

Those who have taken any part in deciding questions affecting wages or trade conditions have found the need of some standard to appeal to, and felt the danger likely to arise from giving decisions either less or more favourable to either party than had been given in other districts in similar circumstances.
In an analogous way, decisions of the prize court of one country are quoted in the courts of other countries, although they are not binding on them.

International Law did exist, and had an important practical influence.