Karl Nickerson Llewellyn (May 22, 1893 – February 13, 1962) was a prominent American jurisprudential scholar associated with the school of legal realism. The Journal of Legal Studies has identified Llewellyn as one of the twenty most cited American legal scholars of the 20th century.
Karl Llewellyn was born on May 22, 1893, in Seattle, but grew up in Brooklyn. He attended Yale College and Yale Law School, where he served as editor-in-chief of the Yale Law Journal. He studied under Arthur Linton Corbin, whose influence on him was profound.
Llewellyn was studying abroad at the Sorbonne in Paris when World War I broke out in 1914. He was sympathetic to the German cause and traveled to Germany to enlist in the German army, but his refusal to renounce his American citizenship made him ineligible. He was allowed to fight with the 78th Prussian Infantry Regiment, and was injured at the First Battle of Ypres. For his actions, he was promoted to sergeant and decorated with the Iron Cross, 2nd class. After spending ten weeks in a German hospital at Nürtingen, and having his petition to enlist without swearing allegiance to Germany turned down, Llewellyn returned to the United States and to his studies at Yale in March 1915. After the United States entered the war, Llewellyn attempted to enlist in the United States Army, but was rejected because he had fought on the German side.
Llewellyn joined the Columbia Law School faculty in 1925, where he remained until 1951, when he was appointed professor of the University of Chicago Law School. While at Columbia, Llewellyn became one of the major legal scholars of his day. He was a major proponent of legal realism. He also served as principal drafter of the Uniform Commercial Code (UCC).
Llewellyn died in Chicago of a heart attack on February 13, 1962.
Compared with traditional jurisprudence, known as legal formalism, Llewellyn and the legal realists proposed that the facts and outcomes of specific cases composed the law, rather than logical reasoning from legal rules. They argued that law is not a deductive science. Llewellyn epitomized the realist view when he wrote that what judges, lawyers, and law enforcement officers "do about disputes is, to my mind, the law itself" (Bramble Bush, p. 3).
As one of the founders of the U.S. legal realism movement, he believed that the law is little more than putty in the hands of a judge who is able to shape the outcome of a case based on personal biases.