Peter H. Irons (born 1940) is an American political activist, civil rights attorney, legal scholar, and professor of political science. Irons is a graduate of Antioch College, an early incubator of progressive politics after World War II. He embarked on his current path in 1963 when he was issued a 3 year sentence at the Federal Correctional Institution in Danbury, Connecticut for refusing military induction. It was while serving his sentence that he became associated with another famous activist, Howard Zinn. He wrote to Zinn, who wrote back, sending him books on civil liberties and American politics. His conviction was ultimately reversed by a federal judge on the ground of prosecutorial misconduct. Later, President Gerald Ford granted him a pardon for refusing induction.

Irons went on to complete his doctorate at Boston University in 1973. Afterwards, Dr. Zinn helped arrange for Irons to work at a law firm defending Daniel Ellsberg, who was under federal prosecution at the time for stealing the Pentagon Papers. His work at the law firm would later serve as motivation for him to pursue a law degree from Harvard Law School.

Upon graduating, he taught at Boston College Law School and the University of Massachusetts before moving to the University of California at San Diego in 1982 where he would establish the Earl Warren Bill of Rights Project, of which he is the director. In addition to teaching and authoring several books, he has also helped reopen the wartime internment cases of Fred Korematsu, Min Yasui, and Gordon Hirabayashi.

He is an Emeritus Professor of Political Science at the University of California, San Diego and an author on legal history. He retired from the University in 2004 and now devotes some of his time to causes that interest him. He has undertaken some legal work in issues of the separation of church and state and written some articles for the Montana Law Review.