A member of a distinguished Sephardic Jewish family, Cardozo enjoyed an unblemished personal reputation, although his father, Albert Jacob Cardozo, a New York Supreme Court justice with Tammany Hall connections, had resigned in 1872 under threat of impeachment. Admitted to the New York bar in 1891, Benjamin Cardozo was highly successful as a courtroom lawyer despite his mild, reserved manner. Elected to the state Supreme Court as a reform candidate in 1913, he was quickly promoted to the Court of Appeals. During his tenure, the quality of this appellate bench was thought by many to exceed that of the Supreme Court. In MacPherson v. Buick Motor Company (1916), Cardozo announced a doctrine that was later adopted elsewhere in the United States and Great Britain: an implied warranty of safety exists between a manufacturer and a private purchaser, despite intermediate ownership of the product by a retail dealer. His decision in Palsgraf v. Long Island Railroad Co. (1928) helped to redefine the concept of negligence in American tort law.

After the resignation of Justice Oliver Wendell Holmes (Holmes, Oliver Wendell) in 1932, President Herbert Hoover (Hoover, Herbert) appointed Cardozo to the United States Supreme Court. In the New Deal period under President Franklin D. Roosevelt (Roosevelt, Franklin D.), Cardozo usually sided with the liberally inclined justices Louis D. Brandeis (Brandeis, Louis) and Harlan Fiske Stone (Stone, Harlan Fiske). He wrote a majority opinion for Helvering v. Davis, 301 U.S. 619, and other social security cases (1937), upholding the federal Social Security program on the basis of the general welfare provision of the United States Constitution (Constitution of the United States of America) (Article I, section 8). In Palko v. Connecticut, 302 U.S. 319 (1937), a criminal case involving a claim of double jeopardy, he held that the Fourteenth Amendment (1868) to the Constitution imposed on the states only those provisions of the Bill of Rights (Rights, Bill of) (the first 10 amendments) that were “of the very essence of a scheme of ordered liberty.” Although it offered a minimum of guidance and may have encouraged much more constitutional litigation than would a specific standard, this test was retained by the court through the 1960s. In 1969, however, the Supreme Court reversed the Palko ruling, holding in Benton v. Maryland that the rule against double jeopardy was so fundamental to justice as to be a requirement of due process of law.

Aside from his published opinions, Cardozo is noted for his jurisprudential work, especially The Nature of the Judicial Process (1921), based on lectures he delivered at Yale University. He was also among the early leaders of the American Law Institute, which was created to “promote the clarification and simplification of the law and its better adaptation to social needs, to secure the better administration of justice, and to encourage and carry on scholarly and scientific legal work.”