This section is from the book "Science Of Legal Method", by Ernest Bruncken. Also available from Amazon: Science of Legal Method.
What is the cause of these similar results thus outlined? The common cause is found in two deep-rooted but fallacious beliefs.
The beliefs, first, that the productive power of custom is extinguished through codification; second, that there is no conscious element or deliberate act of the will in the creation of customary or extra-legislative law-these two fallacies have led up necessarily to the conclusion that legislation alone (as contrasted with the settled doctrines of the courts and of legal writers) contains an element of policy, and that the results, therefore, of the study of "legislative policy" can be utilized only by the lawmaker. The very term "legislative policy" translates the widespread conviction that its applications are limited to the field of legislation.
But these two premises, which are the basis of that conclusion, are both fallacious. I have already expressed my views upon the first of them, that is, the immobility of law merely as a result of codification, and have noted a few of the more striking refutations which the theory has received at the hands of actual facts. I therefore merely refer the reader to these prior explanations.
But I have not yet critically examined the second of these premises, viz., the absolute spontaneity which is claimed to characterize customary law, as contrasted with legislation,-that is, unwritten law as opposed to written law. The terms "spontaneous" or "natural" movement of law designate conveniently the extra-legislative or customary production of juridical rules, but do not connote the distinctions and reservations which attach to the idea contained in these expressions. We must now critically examine the validity of this current notion concerning the nature of the extra-legislative sources of law. For the field of application of "legal policy" will be extraordinarily broadened, if it comes to be generally recognized that to predicate complete unconsciousness in extra-legislative production is a mere assumption without foundation in reason. It is due to a spread through European thought of a wholly artificial conception of custom, - a notion foreign to countries which live under a system of customary law, or where the conception has gained but slight foothold through foreign importations that have never been assimilated. This notion has thrived in surroundings subject to the domination of statutory law and deeply hostile to custom.