The Obama administration's decision this week to try and block a controversial new law in Arizona targeting illegal immigrants sets the stage for an important legal and constitutional clash between the federal government and one of the 50 U.S. states.
At issue is a new state law in Arizona that goes into effect later this month requiring police to check a person's immigration status if the officer has reason to believe the individual is in the country illegally.
The law was passed after years of frustration in Arizona in dealing with an estimated 460,000 illegal immigrants and amid complaints that the federal government was not doing enough to protect the border with Mexico.
The Justice Department decision to try and block the Arizona law in court sets up a classic constitutional confrontation between the power of the central government in Washington and the rights of individual states to act on their own behalf.
Richard Friedman is an expert on constitutional law at the University of Michigan Law School.
"I mean I do think that this conflict is characteristically American that is of the United States and of our constitutional structure," said Richard Friedman. "We have state governments, which have general authority to regulate the affairs of the people within their states. And then superimposed on top of them is the federal government, which is supreme but only with respect to matters that are entrusted to it."
Under the U.S. Constitution, the federal government in the form of the Congress and the president are empowered to provide for the national defense, conduct foreign policy and raise money to fund government spending. But the Tenth Amendment to the Constitution says that any powers not delegated to the central government are reserved to the states, and that has led to some legal clashes throughout history.
Expert Richard Friedman says most constitutional scholars believe that the power to regulate immigration rests with the federal government, not the states.
"The federal government is supreme within its proper jurisdiction," he said. "In other words, if a particular subject is one on which Congress can regulate, then federal law is the supreme law of the land and any state law that interferes with that is invalid. And immigration has long been understood to be a matter for federal law. So the question really is whether the state law obstructs with or conflicts with or interferes with federal law."
Several civil rights groups are also challenging the Arizona law in federal court, arguing that the statute could lead to racial profiling by police on the lookout for suspected illegal immigrants. Arizona officials counter that the law includes language that forbids racial profiling and argue that the law will not have a discriminatory impact.
Arizona Governor Jan Brewer dismissed the Justice Department's lawsuit as a massive waste of taxpayer money and said her state was forced to act because the federal government has failed to protect the country's borders.
American University legal expert Steve Vladeck says supporters of the Arizona law welcome the legal and constitutional showdown about to play out in the federal courts.
"From the moment that the Arizona legislature passed this law, part of the goal was to provoke this exact response-the federal government suing to stop the law," said Steve Vladeck. "I think the whole issue here is whether the states have the power to take these kinds of measures against undocumented immigrants, and so I think the entire plan was to force the federal government to take a position one way or the other."
Several other states are also considering laws targeting illegal immigrants and a recent Pew Research Center national poll found that more than 60 percent of Americans approve of the Arizona law. Political experts believe immigration could be a potent issue in this year's midterm congressional elections.
Conservative legal analyst Colby May of the American Center for Law and Justice says many states are closely watching the legal battle over the Arizona immigration law.
"And until, in fact, the federal government shoulders its responsibility and does what the American people have been urging it to do for quite some time, which is control the border, you are still going to find lots and lots of folks coming in illegally into the United States and states are going to feel pressure in their social services and in education and in so many other ways that they are probably going to feel a need to react and do something," said Colby May.
The court battle over the Arizona law will likely play out over the next several months at least, and many legal experts predict that the issue will eventually find its way to the Supreme Court, which has the final word on interpreting the U.S. Constitution and settling legal conflicts between the states and the central government in Washington.