The American Law Institute (ALI) is a research and advocacy group of judges, lawyers, and legal scholars established in 1923 to promote the clarification and simplification of United States common law and its adaptation to changing social needs. Members of ALI include law professors, practicing attorneys, judges and other professionals in the legal industry. ALI writes documents known as "treatises", which are summaries of state common law. Many courts and legislatures look to ALI's treatises as authoritative reference material concerning many legal issues. However, some legal experts and the late Supreme Court Justice Antonin Scalia, along with some conservative commentators, have voiced concern about ALI rewriting the law.

John Henry Wigmore (1863–1943) was an American lawyer and legal scholar known for his expertise in the law of evidence and for his influential scholarship. Wigmore taught law at Keio University in Tokyo (1889–1892) before becoming the first full-time dean of Northwestern Law School (1901–1929). His scholarship is best remembered for his Treatise on the Anglo-American System of Evidence in Trials at Common Law (1904), often simply called Wigmore on Evidence, and a graphical analysis method known as a Wigmore chart. He served as the second president of the American Association of University Professors.