A federal judge on Wednesday blocked some of the toughest provisions in the Arizona illegal immigration law, putting on hold the state's attempt to have local police enforce federal immigration policy.
Though the rest of the law is still set to go into effect Thursday, the partial injunction on SB 1070 means Arizona, for the time being, will not be able to require police officers to determine the immigration status of anyone they stop or arrest.
U.S. District Judge Susan Bolton also struck down the section of law that makes it a crime not to carry immigration registration papers and the provision that makes it a crime for an illegal immigrant to seek or perform work.
Arizona Gov. Jan Brewer, reacting to the ruling, said the "fight is far from over" and vowed to take the case "all the way to the Supreme Court if necessary."
"The bottom line is we've known all along that it is the responsibility of the feds," Brewer told The Associated Press. "They haven't done their job so we were going to help them do that."
The Mexican government praised the judge's decision. Foreign Minister Patricia Espinosa told reporters that the injunction was a "first step in the right direction."
In all, Bolton struck down four sections of the law, the ones that opponents called the most controversial. Bolton said she was putting those sections on hold until the courts resolve the issues.
The ruling said the Obama administration, which sought the injunction, is likely to "succeed on the merits" in showing the above provisions are preempted by federal law.
"The court by no means disregards Arizona's interests in controlling illegal immigration and addressing the concurrent problems with crime including the trafficking of humans, drugs, guns, and money," the ruling said. "Even though Arizona's interests may be consistent with those of the federal government, it is not in the public interest for Arizona to enforce preempted laws."
A number of provisions will still go into effect as the case is litigated. Arizona will be able to block state officials from so-called "sanctuary city" policies limiting enforcement of federal law; require that state officials work with federal officials on illegal immigration; allow civil suits over sanctuary cities; and make it a crime to pick up day laborers.
The ruling came just as police were making last-minute preparations to begin enforcement of the law and protesters were planning large demonstrations to speak out against the measure. At least one group planned to block access to federal offices, daring officers to ask them about their immigration status.
Justice Department spokeswoman Hannah August said the court "ruled correctly" with its decision Wednesday.
"While we understand the frustration of Arizonans with the broken immigration system, a patchwork of state and local policies would seriously disrupt federal immigration enforcement and would ultimately be counterproductive," August said.
The Department of Homeland Security released a statement saying the decision "affirms the federal government's responsibilities" to enforce immigration law. The department claimed "unprecedented resources" have been devoted to that effort.
Rep. Luis Gutierrez, D-Ill., one of the most vocal advocates on immigration issues on Capitol Hill, applauded the decision.
"Arresting people based on their appearance and holding them until you can investigate their immigration status is patently un-American and unconstitutional," he said.
But supporters of the policy slammed the court's decision.
"This fight is far from over. In fact, it is just the beginning, and at the end of what is certain to be a long legal struggle, Arizona will prevail in its right to protect our citizens," Brewer said.
Rep. Darrell Issa, R-Calif., called the ruling "misguided."
"The federal government has a right and a responsibility to enforce existing laws, but when they fail to meet that responsibility, we should not stand in the way of the states that take action to respond to the very real threat of border violence, drug cartels and human smuggling," he said in a written statement. "There's nowhere in the Constitution that says a state is limited to what it absolutely won't do and can be stopped for what it might do and to exercise a judgment against a state that has passed a law that is consistent with existing federal law is beyond absurd."
The volume of the protests will likely be turned down a few notches because of the ruling by Bolton, a Clinton appointee who suddenly became a crucial figure in the immigration debate when she was assigned the seven lawsuits filed against the Arizona law.
Lawyers for the state contend the law was a constitutionally sound attempt by Arizona -- the busiest illegal gateway into the country -- to assist federal immigration agents and lessen border woes such as the heavy costs for educating, jailing and providing health care for illegal immigrants.
Opponents argued the law will lead to racial profiling, conflict with federal immigration law and distract local police from fighting more serious crimes. The U.S. Justice Department, civil rights groups and a Phoenix police officer had asked the judge for an injunction to prevent the law from being enforced.
Localities inside Arizona were already preparing to interpret the law in different ways. The Tucson Unified School District's Governing Board approved by a 5-0 vote a policy Tuesday that maintains the district's stance of not enforcing immigration laws in the district's schools.
The hardest-line approach was expected in the Phoenix area, where Maricopa County Sheriff Joe Arpaio plans his 17th crime and immigration sweep. He planned to hold the sweep regardless of the ruling.
Arpaio, known for his tough stance against illegal immigration, plans to send out about 200 deputies and volunteers who will be looking for traffic violators, people wanted on criminal warrants and others. He has used that tactic before to arrest dozens of people, many of them illegal immigrants.
"We don't wait. We just do it," he said. "If there's a new law out, we're going to enforce it."
Elsewhere in the state, police officials were busy wrapping up training sessions this week. Many of the state's 15,000 police officers have been watching a DVD released this month that signs that might indicate a person is an illegal immigrant are speaking poor English, looking nervous or traveling in an overcrowded vehicle. It warned that race and ethnicity do not.
Some agencies added extra materials, including a test, a role-playing exercise or a question-and-answer session with prosecutors.
The Associated Press and Reuters contributed to this report.