The planned appeal to the high court comes after Brewer lost an appeal April 11, when a three-judge panel of the 9th Circuit Court of Appeals refused to reverse a lower court's order that prevented key parts of the law from being enforced.
The panel said federal officials were likely to prove the law is unconstitutional and succeed in their argument that Congress has given the federal government sole authority to enforce immigration laws.
Brewer's lawyers argued the federal government hasn't effectively enforced immigration law at the border and in Arizona's interior and that the state's intent in passing the law was to assist federal authorities as Congress has encouraged.
They also argued U.S. District Court Judge Susan Bolton erred by accepting speculation by the federal government that the law might burden legal immigrants and by concluding the federal government would likely prevail.
The U.S. Justice Department urged the appeals court to uphold the order that blocked enforcement of parts of the law.
The federal government argued the law intrudes on its exclusive authority to regulate immigration, disrupts relations between the United States and Mexico, hinders cooperation between state and federal officials, and burdens legal immigrants.
Less than a day before the law was to take effect in July, Bolton blocked key provisions from being enforced, including requirements that immigrants get and carry immigration registration papers and that police -- in enforcing other laws -- question the immigration status of those they suspect are in the country illegally. But Bolton let other parts take effect, such as a ban on obstructing traffic while seeking or offering day-labor services on streets.
The law was passed in April 2010 amid years of complaints that the federal government hasn't done enough to lessen the state's role as the nation's busiest illegal entry point. Its passage inspired protests and led to lawsuits seeking to overturn the law and a debate about whether the law would lead to racial profiling.
The Arizona law isn't the only one that has challenged federal primacy in immigration.
The U.S. Supreme Court is mulling arguments in an appeal by groups that are trying to overturn a 2007 Arizona law that prohibits employers from knowingly hiring illegal immigrants.
Civil rights groups have filed a lawsuit aimed at halting a new immigration law in Utah, saying it is too much like portions of Arizona's immigration law.
For more news from KSAZ in Phoenix, go to www.myfoxphoenix.com.