"I like the United States a lot but the Arizona law is not good. The vender asked me for my ID [identification] and I gave her my work permit. Soon after that the police came. It was like I killed someone," said Foungounou.

Foungounou was in the U.S. legally, but he did what Arizona officials hope to accomplish with the law. Arizona shares a border with Mexico. Governor Jan Brewer said she wanted to make conditions so uncomfortable that illegal immigrants would voluntarily leave her state. The law requires legal immigrants to carry documentation with them at all times or be jailed. It also requires police to check a person's immigration status if the officer suspects the individual is in the country illegally.

The law was to end years of frustration over Arizona's estimated 460,000 illegal immigrants. After several court challenges, its future is up to the U.S. Supreme Court.

Michael McLaughlin said the law is refreshing and should be upheld. His wife is a German immigrant who followed the legal path to citizenship 42 years ago.

He and other volunteers are trying to get strict laws in all 50 states. They plan to demonstrate in front of the Supreme Court.

"We have about 8 million illegal aliens in the United States, 7 million of whom are working in non-agricultural jobs at the same time that we have 22 million Americans looking for full-time employment," said McLaughlin.

If the Supreme Court upholds the law, individual states could enact their own immigration rules. Kristina Campbell is a law professor at the University of the District of Columbia.

"They really are opening up a can of worms if you believe in the principle of federalism - that we are several states, but one nation. We have the same laws at the federal level. Then, I think turning around and saying, 'Well you guys can do whatever you want on this particular issue' is problematic."

Ali Noorani of the National Immigration Forum opposes the law, but he sees the benefit of getting the nation to address immigration.

"You know what? We've got to get our act together. We've got to figure this out. Whether it is Arizona or Alabama, the country is losing because we have a dysfunctional immigration system," said Noorani.

The justices are expected to have a decision in June.