The Federal Courts' Gate-Keeping Function for Fixed and Invariable Evidence of Custom and Usage

Reliable knowledge of the customs and practices of a particular industry can be useful in the interpretation of contracts, including those that provide insurance. See Appleman on Insurance Law & Prac. 2d '5.7 (2005); Richard A. Lord, Usage and Custom, in 12 Williston on Contracts '34:2 (4th ed. 2005). The roots of the doctrine stretch back to 13th and 14th century efforts by English jurists to incorporate the law of merchants (derived from customs) into the general common law. See generally Charles A. Bane, From Holt and Mansfield to Story to Lewellyn and Mentschickoff: The Progressive Development of Commercial Law, 37 U. Miami L. Rev. 351, 352-62 (1983). This English effort spread to the United States and eventually culminated in the creation of the Uniform Commercial Code, which both codified the law of merchants and left room for its development and expansion through the continued evolution of customs and practices. See Uniform Commercial Code '1-102. In keeping with the general view of the Code's primary drafter (Karl Lewellyn), the Code deals with questions of “custom” and “usage” as matters of fact instead of questions of law. See Bane, 37 U. Miami L. Rev. at 376.