Richard Allen Posner

Richard Allen Posner (; born January 11, 1939) is an American legal scholar and retired United States circuit judge who served on the U.S. Court of Appeals for the Seventh Circuit from 1981 to 2017. Posner was appointed by President Ronald Reagan, and he served as the chief judge of the Seventh Circuit from 1993 to 2000. A former law professor at the University of Chicago, Posner was identified in The Journal of Legal Studies as the most-cited legal scholar of the 20th century. As of 2021, he is also the most-cited American legal scholar of all time. He is widely considered to be one of the most influential legal scholars in the United States.

Posner is known for his scholarly range and for writing on topics outside of law. In his various writings and books, he has addressed animal rights, feminism, drug prohibition, same-sex marriage, Keynesian economics, law and literature, and academic moral philosophy, among other subjects.

Posner is the author of nearly 40 books on jurisprudence, law and economics, antitrust law, and several other topics, such as Economic Analysis of Law, The Economics of Justice, The Problems of Jurisprudence, Sex and Reason, Law, Pragmatism and Democracy, and The Crisis of Capitalist Democracy. Posner has generally been identified as being politically conservative; towards the end of his tenure on the bench, however, he distanced himself from the positions of the Republican Party, authoring more liberal rulings involving same-sex marriage and abortion. In A Failure of Capitalism, he writes that the 2008 financial crisis caused him to question the rational-choice, laissez-faire economic model that lies at the heart of his law and economics theory.