Any conclusion about the desirability or the practicability of codifying international law ought to be based on a clear idea of what the process would involve, and unfortunately "codification" is an ambiguous word. In the sense in which British and American lawyers use the word it relates to the form in which the law is presented. When we codify, we do not regard the task as one of improving the substance of the law, but as one of collecting the existing rules and stating them concisely and clearly. It is true that, even so, the work must involve some element of law-creating, for when we examine the materials on which we have to work, the customary rules, the judicial precedents, the particular statutes or conventions, we inevitably come across points on which no authority exists, or on which the existing authorities are conflicting, and it would be pedantic to insist that, because codification is concerned only with the form of the law, these defects should be reproduced in the finished code. Where the authorities are in conflict therefore, the codifier must choose the rule which seems the most desirable; where there are gaps in the existing law, he must suggest a new rule to fill them. To that extent codifiers must legislate. But it is only a limited extent. In the main, the work is not one of legislation, but of careful drafting. The few examples that we in England have of codification have been of this type. We have codified our law of sale of goods, and of bills of exchange in this way, and the result has been to tidy up the law on these topics. But that is its only important effect. It has not provided the layman with a sort of legal ready-reckoner, which many people seem to think a code ought to be able to do; and for the practising lawyer the chief difference is that instead of deducing the applicable rule from the decisions, he now uses the decisions to explain and illustrate the statutory rule.
James L. Brierly,
THE CODIFICATION OF INTERNATIONAL LAW,
Mich. L. Rev.
Available at: https://repository.law.umich.edu/mlr/vol47/iss1/3