A federal judge has blocked one of the most controversial sections of a tough Arizona immigration law, granting a preliminary injunction Wednesday (July 28) that prevents police from questioning people about their immigration status.

That provision of the law requires police to "make a reasonable attempt to determine the immigration status of a person stopped, detained or arrested" if the officer has a reasonable suspicion that the person is in the United States illegally.

U.S. District Judge Susan Bolton's ruling, in response to a motion filed by the federal government, came with scant hours to go before the law goes into effect.

She also blocked provisions of the law making it a crime to fail to apply for or carry alien registration papers or "for an unauthorized alien to solicit, apply for, or perform work," and a provision "authorizing the warrantless arrest of a person" if there is reason to believe that person might be subject to deportation.

DHS Reacts:

Statement by Deputy Press Secretary Matt Chandler

“The court’s decision to enjoin most of SB1070 correctly affirms the federal government’s responsibilities in enforcing our nation's immigration laws. Over the past eighteen months, this Administration has dedicated unprecedented resources to secure the border, and we will continue to work to take decisive action to disrupt criminal organizations and the networks they exploit. DHS will enforce federal immigration laws in Arizona and around the country in smart, effective ways that focus our resources on criminal aliens who pose a public safety threat and employers who knowingly hire illegal labor, as well as continue to secure our border.

“ICE works everyday with local law enforcement across the country to assist them in making their communities safer and we will continue do so in Arizona. At the same time, we will continue to increase resources in Arizona by complementing the National Guard deployment set to begin on Aug. 1 with the deployment of hundreds of additional Immigration and Customs Enforcement agents, Border Patrol agents and other law enforcement personnel that will aid in our continuing efforts to conduct outbound inspections, patrol challenging terrain, and interdict illicit smugglers. We are focused on smart, effective immigration and border enforcement while we work with Congress toward the type of bipartisan comprehensive reform that will provide true security and establish accountability and responsibility in our immigration system at the national level.”