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A Latinx Resource Guide: Civil Rights Cases and Events in the United States

1975: U.S. v. Brignoni-Ponce

"The likelihood that any given person of Mexican ancestry is an alien is high enough to make Mexican appearance a relevant factor, but standing alone it does not justify stopping all Mexican-Americans to ask if they are aliens."

—Justice Lewis Powell

Robert S. Oakes, Photographer, Official portraits of the 1976 U.S. Supreme Court: Justice Lewis F. Powell, Jr. 1976. Library of Congress Prints and Photographs Division.

Racial profiling along the Mexico-United States border had enabled Border Patrol agents to stereotype, stop, and associate individuals with “Mexican looking” ancestry with suspected criminal activity. On June 30, 1975, The U.S. Supreme Court issued its opinion on United States. v. Brignoni-Ponce (1975) and ruled that stopping individuals for unreasonable suspicions violated the 4th Amendment of the U.S. Constitution

On March 11, 1973, a fixed checkpoint located in San Clemente, California, was closed, leading Border Patrol agents to monitor traffic on a roving patrol. The agents stopped Mr. Brignoni-Ponce, on the basis of his Mexican appearance. Brignoni-Ponce was caught, arrested, and trialed for transporting undocumented individuals. On his criminal trial, Brignoni-Ponce’s attorney cited violation of constitutional rights under the 4th Amendment, which states that search and seizure without a warrant may only be conducted with a reasonable and probable cause, and based his argument on the exclusionary rule, which dismisses any evidence gathered from an unconstitutional search. Brignoni-Ponce appealed to the Ninth Circuit Court of Appeals, which ruled that Mexican appearance is not a reasonable and probable cause for Border Patrols when stopping vehicles and that under the exclusionary rule, all evidence—including the testimony of the undocumented individuals found on the scene—was gathered illegally.

The United States appealed to the Supreme Court on October 15, 1974 and based their argument on Section 287(a)(1) and 287(a)(3) of the Immigration and Nationality Act, which authorizes agents to interrogate individuals believed to be undocumented and warrantless searches “within a reasonable distance” from the border. Justice Powell issued the Court’s majority opinion, which held that the 4th Amendment requires a reasonable suspicion for stopping and interrogating a vehicle and its passengers. Moreover, the Supreme Court ruled that an individual’s sole appearance—without any other reasonable factors that could incite suspicion—did not permit INS agents to stop individuals and revoked any evidence gathered from Mr. Brignoni-Ponce’s illegal search.


May 26, 1924 The Immigration and Nationality Act of 1924 established the Border Patrol.
March 11, 1973 Mr. Brigoni-Ponce was stopped due to his Mexican appearance and caught transporting undocumented individuals.
June 14, 1974 The Ninth Circuit Court issued their opinion and ruled Mr. Brigoni-Ponce’s search and interrogation unconstitutional under the 4th Amendment.
October 15, 1974 The United States appealed to the Supreme Court.
June 30, 1975 The Supreme Court ruled Brigoni-Ponce's interrogation and search unconstitutional for having no reasonable suspicion or cause.


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