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

2012: Arizona v. United States

Carol M. Highsmith, photographer. The U.S. side of a border wall between the United States and Mexico in Douglas, a city on the Mexican border in southeastern Arizona. 2018. Library of Congress Prints and Photographs Division.

Arizona v. United States (2012) was a U.S. Supreme Court case addressing Arizona Senate Bill 1070. On April 23, 2010, Arizona Governor Jan Brewer signed S.B. 1070 (also known as the Support Our Law Enforcement and Safe Neighborhoods Act). It authorized state and local law enforcement to arrest individuals without a warrant under “reasonable suspicion”. The bill also required individuals police stopped or detained to show a form of identification. Additionally, S.B. 1070 made it a crime to transport or harbor undocumented immigrants, strengthened sanctions against employers who hired unauthorized employees, and prohibited localities from passing ordinances that would obstruct state law enforcement from enforcing federal immigration laws.

A coalition of groups challenged the Arizona bill, including the Mexican-American Legal Defense Education Fund (MALDEF), the ACLU of Arizona, the Arizona Association of Chiefs of Police, and the Tohono O’odham Nation. According to the law’s opponents, S.B. 1070 intervened with federal jurisdiction over immigration, violated the Supremacy Clause of the U.S. Constitution, encouraged racial profiling, and hampered police-citizen relationships.The Arizona Senate bill led to lawsuits filed by organizations, cities, the country of Mexico, and the U.S. Department of Justice.

On July 28, 2010, U.S. District Judge Susan Bolton ruled on an injunction against the bill and blocked four key S.B. 1070 provisions. The State of Arizona appealed the ruling, and the Court of Appeals for the Ninth Circuit rejected the appeal in April 2011. Subsequently, Arizona Governor Jan Brewer appealed the case to the U.S. Supreme Court. On June 25, 2012, Associate Justice Anthony Kennedy gave the court’s majority opinion on Arizona v. U.S. (2012) and declared most of S.B. 1070 unconstitutional under the federal government’s preemptive power over immigration except for section 2(B)—known as the “Show Me Your Papers” provision—permitting law enforcement to inspect the immigration status of individuals under reasonable suspicion.

The Show Me Your Papers law has been subject to controversy for racial profiling against individuals of color in violation of the Equal Protection Clause of the 14th Amendment.

Four Critical Provisions Under Arizona's S.B. 1070

Section 2(B): Also known as the “Show Me Your Papers” provision. Any individual stopped or detained for “reasonable suspicions” of being undocumented must show proof of their immigration status to law enforcement. UPHELD

Section 3: Makes it a state misdemeanor to fail to carry “alien registration document”. STRUCK DOWN

Section 5(C): Makes it a misdemeanor to seek or be employed within the state while lacking work authorization. STRUCK DOWN

Section 6: Allows law enforcement officers to arrest an individual without a warrant if the office has a “probable cause” to believe the individual has committed a crime subject to deportation. STRUCK DOWN


1996 The US government signs Illegal Reform and Responsibility Act (IIRA), prohibiting unauthorized immigrants from federal, state, and local benefits. Section 287(G) of the IIRA allows certain trained state and local law enforcement to implement immigration policies.
1997 Chandler, Arizona ratifies Operation Restoration, permitting local police to detain individuals and request proof of U.S. citizenship.
2004 A group of civilians establish the Minuteman Project to monitor the arrival of immigrants at the United States-Mexico border.

Arizonans pass a series of anti-immigrant propositions. New statues deny non-citizens bail, prohibit undocumented employees from filing lawsuits, and prevent undocumented students from receiving in-state tuition or financial aid. The US government also enacts the Secure Fence Act, allowing the construction of 700 miles of a border wall between the U.S. and Mexico.

2007 Governor Janet Napolitano signs House Bill 2779, requiring employers to verify their employees’ immigration status.
April 19, 2010 The Arizona State Legislature passes S.B. 1070 also known as the “Support Our Law Enforcement and Safe Neighborhoods Act”, which Rusell Pearce introduced.
April 23, 2010 Governor Jan Brewer signs S.B. 1070 (Support Our Law Enforcement and Safe Neighborhoods Act) into law.
July 14, 2010 The Tohono O'odham Nation files Friendly House, et al v. Michael Whiting, et al., challenging Arizona's controversial anti-immigration law.
July 28, 2010 Judge Susan Bolton issues a preliminary injunction against four provisions included on the bill. Arizona’s government appeals the district court’s ruling to the U.S. Court of Appeals for the Ninth Circuit.
April 11, 2011 The U.S. Court of Appeals for the Ninth Circuit upholds Judge Susan Bolton’s injunction. Arizona’s government appeals to the U.S. Supreme Court.

June 2012 The United States Supreme Court rules against three provisions of S.B. 1070 and preserves section 2(B) of the provision, allowing law enforcement to stop or detain individuals under reasonable suspicions and request citizenship identification.
September 2012 The American Civil Liberties Union (ACLU), the National Immigration Law Center (NILC) and the Mexican–American Legal Defense and Educational Fund (MALDEF) file for an injunction against the Court’s decision, arguing on section 2(B)’s violation of the Equal Protection Clause of the 14th amendment. Judge Susan Bolton rejects the injunction against the Supreme Court’s ruling.


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