[2] The bill's passage immediately sparked constitutional concerns over potential civil rights violations and encouraging of racial profiling.
[6][7][8] A rally in Los Angeles, attended by Cardinal Roger Mahony of the Roman Catholic Church, attracted between 50,000 and 60,000 people, with protesters waving Mexican flags and chanting "Sí se puede.
[7][8] There and in some other locations, demonstrators expressed frustration with what they saw as the administration's lack of action on immigration reform, with signs holding messages such as "Hey Obama!
"[11] Additionally, the Justice Department, in its July 6, 2010, motion, requested for the federal courts to issue an injunction to enjoin enforcement of the law before it went into effect.
"[16] The Latin American countries of Argentina, Bolivia, Chile, Colombia, Costa Rica, El Salvador, Guatemala, Mexico, Nicaragua, Paraguay, and Peru filed an amicus brief in support of the United States.
[22] On April 11, 2011, the Ninth Circuit panel upheld the district court's ban on parts of the law taking effect, thus ruling in favor of the Obama administration and against Arizona.
[28] The Supreme Court announced in December 2011 that it would review Arizona's Support Our Law Enforcement and Safe Neighborhoods Act,[29][30] and oral arguments took place on April 25, 2012.
The four provisions in question were: Kennedy's opinion embraced an expansive view of the United States Government's authority to regulate immigration and aliens, describing it as "broad" and "undoubted".
That authority derived from the legislative power of Congress to "establish an uniform Rule of Naturalization", enumerated in the Constitution,[41] as well as the longstanding interpretation of federal sovereignty in areas pertaining to the control and conduct of relations with foreign nations.
Under those principles, Section 5 stood as an obstacle to the objectives of Congress of not imposing "criminal penalties on aliens who seek or engage in unauthorized employment".
Section 6 of SB 1070 was also found to be preempted by federal law on the basis that it created an "obstacle to the full purposes and objectives of Congress".
Listing several examples, Justice Kennedy wrote that Section 2(B) "likely would survive preemption" if it is interpreted to require only state officers to conduct a status check "during the course of an authorized, lawful detention or after a detainee has been released."
"[46] To support his position, Justice Scalia reviewed several cases from the early history of the Supreme Court's Immigration jurisprudence.
[45] With respect to Section 5(C) Justice Alito argued that "[t]he Court's holding on §5(C) is inconsistent with De Canas v. Bica, 424 U. S. 351 (1976), which held that employment regulation, even of aliens unlawfully present in the country, is an area of traditional state concern.
"[48] He also argued that Section 6 was not preempted because "[l]ike §2(B), §6 adds virtually nothing to the authority that Arizona law enforcement officers already exercise.
"[48] In an article on SCOTUSblog, Stephen Wermiel mentions that Justice Kagan's recusal may have played a role in the 5–3 outcome of the case.
[49] Shortly after retiring as Solicitor General of the United States, Donald B. Verrilli, Jr. said in a 2016 interview that it was a high-profile case in 2012, but its consequences were not fully appreciated.
"[50] After the Supreme Court ruled on the case, its decision helped to deter other states from establishing and enforcing their own immigration policies.
Verrilli concluded that the Court had made "a very consequential decision" which meant that an incipient anti-immigrant movement "got stopped dead in its tracks".