United States v. Buddenberg was a federal prosecution of four animal rights activists in California for conspiracy to commit animal enterprise terrorism.

On February 19th and 20th, 2008, the Joint Terrorism Task Force of the FBI arrested four animal rights activists as “terrorists.”The indictment against Joseph Buddenberg, Maryam Khajavi, Nathan Pope and Adriana Stumpo (the "AETA 4") charged them with conduct including protesting, chalking the sidewalk, chanting and leafleting, and the alleged use of “the Internet to find information on bio-medical researchers.”These acts are all protected by the First Amendment of the U.S. Constitution.

The indictment was made possible because of a little known law called the Animal Enterprise Terrorism Act (AETA).Passed by Congress in November 2006, the AETA is aimed at suppressing speech and advocacy by criminalizing First Amendment-protected activities such as protests, boycotts, picketing and whistleblowing.It targets animal rights activists, but includes language so broad and vague it could be used to prosecute labor activists who organize a successful boycott of Wal-Mart, or union folks who picket a university cafeteria.Pushed through Congress by a powerful lobby of corporations and research institutions, the AETA is an unconstitutional law because it criminalizes a broad swath of protected First Amendment activities and is so unclear as to fail to give people notice of whether or not their conduct is lawful.On this basis, CCR and the defense team asked the Court to strike down the AETA as unconstitutional.

By filing this motion, CCR attacked the AETA as facially unconstitutional on the grounds of “overbreadth” and “vagueness.”These are doctrines that allow individuals to challenge laws that chill speech and advocacy and require people to guess at a statute's meaning and scope.