Llewellyn (1893–1962) was the most important figure associated with the American Legal Realism of the 1920s and 1930s, which held that the law was indeterminate on the basis of statutes and precedents alone and required study of the how disputes are resolved in practice. The "sociological" wing of legal realism championed by Llewellyn held that in American law dispute resolution was strongly influenced by norms such as those in mercantile practice. Llewellyn and Hoebel (1941) went to on to develop a means of determining legal practice from ethnographic description of trouble cases, including mediation and negotiation as well as adjudication.
Llewellyn (1893–1962) was the most prominent figure connected to American Legal Realism of the 1920s and 1930s, which posited that law was ambiguous based on statutes and precedents alone and necessitated examination of how disputes are resolved in practice. The "sociological" faction of legal realism championed by Llewellyn emphasized that American law's dispute resolution was significantly influenced by norms such as those found in mercantile practice. Llewellyn and Hoebel (1941) went on to develop a method for determining legal practice through ethnographic descriptions of trouble cases, including mediation and negotiation as well as adjudication.