Felix Frankfurter

Frankfurter began private practice with a New York law firm. During his first year he was appointed Assistant U.S. Attorney for the Southern District of New York under Henry Stimson (1867–1950). From Stimson, Frankfurter learned the art of trial preparation, which stressed not only to prepare for your own case but for the opposition's case as well. With his fondness for details, Felix gathered large amounts of credible evidence to support his oral arguments in court. Analyzing legal problems from multiple perspectives became Frankfurter's specialty. Stimson also taught him how to coax reluctant colleagues toward his point of view, a talent he perfected over time. When Stimson was appointed Secretary of War in 1910, Frankfurter accompanied him to Washington, D.C., to work as legal counsel for the Bureau of Insular Affairs.

Frankfurter had an exuberant style and a meticulous legal mind as well as a great deal of confidence in his own abilities to bring about consensus in any situation. Using his personality and keen intellect, he formed close relationships with those in power and used flattery and praise on those he most wanted to please.

In 1914 Frankfurter accepted an appointment to the faculty of Harvard Law School as professor of administrative law. From 1916 until 1918 President Woodrow Wilson (1856–1924; served 1913–21) called on him to investigate a growing number of labor disputes. Because of his outspoken support of individual civil rights and the protection of defendants' rights in criminal trials, he was often viewed as a staunch liberal (believing in the natural goodness of human beings and favoring civil liberties, democratic reform, and social progress).

In 1920 Frankfurter was a founding member of the American Civil Liberties Union (ACLU). The organization was created in response to the Red Scare (the American government and public fear of communism and its perceived threat to American democracy that led to mass arrests of foreigners) following World War I (1914–18; war in which Great Britain, France, the United States, and their allies defeated Germany, Austria-Hungary, and their allies). Communism was seen as a serious threat to American democracy and greatly feared by the public. Government agents arrested large numbers of people and held them indefinitely because of their political beliefs. The ACLU worked to defend the civil rights guaranteed in state and federal constitutions for those detained by law enforcement.