Stevens enlisted in the Navy during World War II. In his position as part of a Navy code-breaking team, Stevens earned the Bronze Star. Following the war, he again followed his father's path and entered Northwestern University Law School to study law. Stevens distinguished himself at Northwestern by becoming editor-in-chief of the school's law review and graduating with the highest grades in the law school's history. After graduating, he served a term as law clerk to Supreme Court Justice Wiley Rutledge.
Stevens joined a prominent law firm in Chicago specializing in antitrust law and creating a reputation as a talented antitrust lawyer. He left the firm to start his own practice after three years and also began teaching law at Northwestern University and the University of Chicago law schools. His abilities in antitrust laws earned him positions with various special counsels to the House of Representatives and the U.S. Attorney General's office.
Stevens became known as a fair-minded and able counsel. Richard Nixon appointed him to the Unites States Court of Appeals for the Seventh Circuit in 1970. On the appeals court, Stevens continued to establish his reputation as a notable legal thinker.
President Gerald Ford appointed Stevens to the U.S. Supreme Court in 1975. As a justice, Stevens has avoided simple conservative or liberal labels. As the Court moved toward the right during the Reagan and Bush presidencies, however, Stevens appeared more and more liberal relative to the make-up of the Court. Although Stevens is difficult to predict, he will typically examine the facts of each case carefully and on its own merits. He also seeks to defer to the judgments of others who he feels are better suited to decide. He has demonstrated considerable judicial restraint and deference to the Congress. Today, Stevens is the most senior justice, both in age and years of service.