The ruling comes as a direct blow to the Obama administration, which challenged the law by saying that no one but an immigration officer could act upon immigration violations. 

About two years ago Arizona passed a law which was intended to discourage illegal immigrants from entering and residing in Arizona known as SB 1070. Among other controversial components, it allowed state police officers to ask about the immigration status of anyone they stopped and arrest those suspected of being illegal immigrants, leading many to say it encouraged racial profiling. The law would have also made it a misdemeanor to not carry immigration papers. 

In July of 2010, Bolton issued an injunction blocking most of these provisions, and the law--and its dissidents--took the case all the way up to the Supreme Court. In June of 2012, the court blocked the majority of the law but decided that allowing police to check the immigration status of those they detained was not against and did not conflict with federal law. 

Arizona governor Jan Brewer, who signed the bill into law, has steadfastly supported the bill and is pleased at the result.

"Certainly Gov. Brewer is pleased with this decision," said spokesman Matthew Benson. "She believes it's time SB1070 is implemented and so that we can see how effective this law is in practice."

Reach Staff Reporter Nandini Ruparel here.