American Civil Liberties Union Law and Legal Definition

American Civil Liberties Union (ACLU) is a membership organization founded in 1920 to defend and protect "the rights of man set forth in the Declaration of Independence and the Constitution." The ACLU researches the legalities of public policies and actions and defends clients in court when civil liberties are in question, without charge and often as amicus curiae (friend of the court). It has committees on academic freedom, state issues, media rights, free speech and association, due process, equal rights, labor/management relations and privacy. It also finances projects on voting rights, reproductive freedom, women's rights, and lesbian and gay rights.