The Arizona immigration bill requires that police seek proof of a person's immigration status if they have a reasonable suspicion that the person is in the country illegally. The law is set to go into effect in January 2011.

Last week, the Mexican government filed an amicus curiae brief [JURIST report] supporting the ACLU suit, claiming a substantial interest in ensuring its "bilateral diplomatic relations" with the US remain "transparent, consistent and reliable, and not frustrated by the actions of individual US states." The government also claims an interest in ensuring that its citizens are "accorded human and civil rights when present in the US in accordance with federal immigration law." Arizona's new immigration law has been widely criticized in regard to the law's constitutionality and alleged "legalization" of racial profiling, since it was signed into law [JURIST report] by Arizona Governor Jan Brewer (R) [official website] in April. In addition to the class action filed by the ACLU, Brewer is also currently facing federal lawsuits filed by the National Coalition of Latino Clergy and Christian Leaders and several Tuscon police officers, who claim they can not properly implement the law without racially profiling. The Obama administration, though supporting immigration reform, has sharply criticized the law [JURIST report], calling it "misguided" and expressing concern that it could be applied in a discriminatory fashion.