But is this Roman and canonical conception of custom acceptable? Ancient as is the tradition which established it, we need not hesitate to reject it. There is a very decisive reason for rejecting the Roman and canonical conception of custom, viz., the impossibility of reconciling it with the actual operation of custom, as observed in the principal systems of customary law in the several great countries where it persists, and in those systems which we may study through the data furnished by the history of western civilizations.
Especially enlightening in this respect is the English system of law (and also that of the great majority of the United States of America) where, alongside statutory law (that is, legislation in the strict sense), which is growing in volume, custom still forms the general foundation of the law.13
English customary law is divisible into two branches of very unequal productivity: first, general custom, whose authority extends over the whole realm, and which is termed the common law, understood in its broad sense, that is, as including equity rather than as distinct from it; second, special or local custom, which applies only to the inhabitants of a more or less restricted region of English soil,14 and for which the term "custom" without qualification is generally employed.
12 Geny, it is true, escapes this last consequence; and none more than he has contributed to win acceptance of the expression "legal policy" in France. This is because his particular theory of the relations of positive law and natural law ("nature des choses positives") made it possible for him to restore to "legal policy" a large circle of influence outside of legislation, in the field reserved by him to natural law.
13 England and the United States are universally cited as the typical example of great nations living principally under a system of customary law; cf. especially, Geny, "Methode d'interpretation et sources en droit prive positif," p. 282.
It is only the second branch of English customary law, or special or local custom, that has felt at all deeply the impress of the Roman and canonical doctrine. Here are discovered not only its distinguishing features (relegated, it is true, to secondary consideration in the English commentaries, but not absent), that is: observance by those affected,15 presumption of a universal implied consent,16 sanction of the sovereign17; but also a series of rules (given prominence in the usual English law treatises), which read sometimes like mere reproductions, at other times like a development or even exaggeration of the measures adopted by the glossators to restrain the domination of custom. Thus it is declared that a custom must be: (1) immemorial; (2) continued; (3) peaceable; (4) reasonable. Local custom is, therefore, rigidly governed by rules which reflect, not without enlargement, the principal features of the Roman and canonical conception.
On the other hand, and for the same reason, the reaction of the canonical doctrine has been almost negligible, or at most has worked but superficially upon that branch of English custom which stands alone to-day as alive and productive, i.e. judicial precedents. General custom, which Blackstone very justly called the "first ground and chief cornerstone of the laws of England," is divided into two great branches: common law, properly speaking, and equity. Neither of these two classes of English customs is susceptible of being bent to the narrow conception which we owe to the imagination of the glossators and canonists.
14 In the definition of special custom I except commercial law -customs of merchants - which is usually classed as such, but which shares in the authority attaching to the common law. Stephen, "New Commentaries on the Laws of England" (1886), i, p. 62.
15 English authors generally do not insist upon this first feature; they merely allude to it in enumerating the conditions necessary for the legality of the custom.
16 Stephen's Blackstone, Introd. sec. 3, ii, 3; Blackstone (ed. Chom-pre),i. p. 121.
17 Blackstone (ed. Chompre), i, p. 116.