CUSTOM. In a legal sense, a custom is a usage which has obtained the force of law. and which will, accordingly, be enforced by time courts. As is explained in the article on CUSTOMARY LAW, the greater part of the legal rules enforced by society are the expression of customs, and custom continues to be an impor tant, though diminishing, source of law in civil ized as well as in primitive society. Indeed, it is only in the progressive communities. where the constantly accelerating progress multiplies social needs faster than they can supplied by the slow processes of enstom, and where the political consciousness has kept pace with this progress, that conscious legal development by legislation and judicial action tends more and more to sup plant the unconscious development of customary law. In the non-progressive societies, which vastly outnumber the progressive, custom is still the principal, if not the only, source of law.
English and American law writers distinguish between gt ne ral and partitular customs, the for mer being of general observance and constituting the body of the common la iv, and the latter being restricted to the inhabitants of a particular dis trict or the members of a certain calling. As an example of the former may lie cited the right of the public to use the seashore, between high and low water mark, for lauding and other lawful purposes; and, as an example of the latter, the right of persons engaged in the business of tow ing, on sonic parts of the river Thames, to go upon the banks of the river for that purpose, though the land is the private property of abut ting proprietors. There is, in truth, and from the point of view of jurisprudence, no distinc tion between the two classes of customs. both depending alike upon immemorial usage, and both, when established, having equally the force of law. In practice, however, the common-law system has made a distinction between them for the purpose of establishing them, the courts taking 'judicial notice' (q.v.) of general customs as a part of the common law which it is their business to interpret and declare, hut requiring proof of the existence of local or other particular customs. But the line between the two classes is not very accurately drawn, the custom of the county of Kent, known as `gavelkind' (q.v.), whereby lands descend to all of the sons equally instead of to the eldest only, and the still more curious custom of 'borough English' (q.v.), under which lands descend to the youngest son in preference to his elder brothers, and which is confined to no particular area, but affects isolated estates or manors in various parts of England, being recognized as parts of the com mon law, notwithstanding their limited occur rence. Doubtless these exceptional eases are to be explained by the great antiquity of the cus toms in question and their early recognition by the courts. Of a similar character is the /cx mereatoria, or custom of merchants, which, though applying only to a limited class in the community. has also become incorporated in the common-law system, and is noticed by the courts without special proof of its terms.
In order that a particular or local usage, al leged to he a custom, shall have the force of law, (1 ) the practice "must have been used so long that the memory of man runneth not to the contrary"—Le. as the phrase is understood in England. from the accession of Richard T. (1 183) : (2) it must have been continued with out interruption: (3) it must have been peace able and acquiesced in. not subject to conten tion and dispute; (4) it must he definite and certain; (5) it must lie reasonable. The pies lion of the reasonableness of a custom is often one of great difficulty. It has been decided that any usage relating to land which is destructive of the land itself, or which deprives the owner of the beneficial use of it, is unreasonable. Thus, a custom for all persons to play games or walk for recreation on private property which has not been dedicated by the owner to public use has been held to lie unreasonable and void; whereas a custom for all the inhabitants of a village to do the same acts has been to be reason aide and protected by law. But a custom for all the inhabitants of a village to pasture cattle on private land is, in its turn, unreasonable. As usually stated, the rule is that a right in the of an easement may arise by eu-stom, bud not a right in the nature of a profit.
It is doubtful whether local or particular ens toms can arise generally in the United States. It has usually been assumed that the common la W rules above set forth are in force in this country, and a few States have so held. It has, on the other band, been decided in New Jersey and Virginia that no rights in another's land can arise by custom, and the decisions have been put upon the ground that there is in the United States no possibility of a usage having the requisite antiquity (i.e. of dating from the reign of Richard 1.) to give it the standing of a cus tom enforceable at law.
The common law makes a further technical distinction between local or particular c u ont and usage, the former being of compulsory legal effect, and the latter consisting of current prac tices, to which parties may or may not conform, and in accordance with which they are supposed to have regulated their conduct or agreements. Thus, in matters of contract, a usage affecting the trade or calling with which the contract has to do may be dealt with as an understood but unexpressed term of the agreement and in mat ters of tort, as an allegation of negligence. the usage of the community (as, e.g. the so-called `rule of the road') may be called into play to determine the presence or absence of negligence. See COMMON LAW; CONTRACT; EASEMENT LAW; PROFIT. Consult: Blackstone, Commen taries on the Lairs of England ; Ele ments of Jurisprudence (9th ed., London, 1 900) ; Holmes, The Corn in on Lame (Boston, 1 88 ) ; Pollock and Maitland, History of the English Law (2d ed., Boston, 1899) ; Gale, Treatise on the Lou' of Easements (7th ed., London. I 899) ; Jones, Treatise on the Construction or Interpreta tion of Commercial and Trade Contracts (New York, 1S86).