This article is from the archive of our partner National Journal

As the Supreme Court prepares to hear oral arguments on Wednesday on Arizona's immigration law, groups for and against the law are scheduling rallies, vigils, press conferences, and hearings in Washington and across the country at a frenzied pace.

The high court will attempt to determine the constitutionality of Arizona's immigration law, known as SB 1070, which requires local law-enforcement officers to ask people's immigration status when they stop them and make warrantless arrests if they believe that person is deportable. 

It's the most high-profile immigration case to hit the Court in years and the stakes are high. Legislatures in at least five other states (Alabama, Georgia, Indiana, South Carolina, and Utah) have passed similar laws. 

The outcome could determine whether states can set immigration laws and whether authorities can enforce them.

As the Supreme Court prepares to hear oral arguments on Arizona's immigration law tomorrow, groups who oppose the law and  those who support it are scheduling rallies, vigils, press conferences and hearings in Washington D.C. and across the country at a frenzied pace.

The court will attempt to determine the constitutionality of Arizona's immigration law, known as SB 1070, which requires local law enforcement officers to ask people's immigration status when they stop them and make warrantless arrests if they believe that person is deportable.  It's the most high-profile immigration case to hit the courts in years and the stakes are high.  Legislatures in at least five other states (Alabama, Georgia, Indiana, South Carolina and Utah) have passed similar laws.  The outcome could determine whether states can set immigration laws and whether state and law authorities can enforce them. At issue is whether four provisions of the Arizona law conflict with federal law or interfere with the federal government's ability to enforce immigration law.  The law requires law enforcement to check the legal status of people who are arrested before they're released and allows officers to stop and arrest anyone they suspect is undocumented; makes it a crime to be in Arizona without legal immigration documents; bans illegal immigrants from applying for a job or working in the state; and allows police to arrest someone without a warrant if they believe that person has committed a crime that could result in their deportation - even if that crime was committed outside the state.  The Justice Department, which filed suit in federal court less than three months after Arizona Governor Jan Brewer signed it into law in April 2010, says that Arizona's law infringes on its authority to set immigration law and conflicts with federal law. Arizona has argued that the law simply complements federal law. Brewer has said that Arizona has borne the brunt of the federal government's failure to enforce current immigration laws, and that SB 1070 is an attempt to protect Arizona's citizenry against crime and costs she says are associated with illegal immigration.  U.S. Sen. Chuck Schumer, D-N.Y. said Tuesday during a judiciary committee hearing that he would introduce legislation to block Arizona's law even if the Supreme Court upholds it. Republican presidential hopeful Mitt Romney has previously said the Justice Department should drop the lawsuit over SB 1070. While the public sees the court case as a broad battle between state and federal interests, tomorrow's arguments will focus on an obscure point of law called implied preemption, said Dan Kowalski, a Texas immigration lawyer and author of Bender's Immigration Bulletin.  Preemption is a legal doctrine that holds that certain matters are national in nature, and, therefore, federal law preempts state or local law. According to Lyle Denniston, author of the SCOTUSblog.com, Arizona has argued that federal immigration law does not directly bar states from passing laws to help enforce those laws and also does not say that states have no role in immigration enforcement because it is solely the responsibility of federal authorities.

At issue is whether four provisions of the Arizona law conflict with federal law or interfere with the federal government's ability to enforce immigration law. 

The law requires law enforcement to check the legal status of people who are arrested before they're released and allows officers to stop and arrest anyone they suspect is undocumented; makes it a crime to be in Arizona without legal immigration documents; bans illegal immigrants from applying for a job or working in the state; and allows police to arrest someone without a warrant if they believe that person has committed a crime that could result in their deportation - even if that crime was committed outside the state. 

The Justice Department, which filed suit in federal court less than three months after Arizona Gov. Jan Brewer signed it into law in April 2010, says that Arizona's law infringes on its authority to set immigration law and conflicts with federal law.

Arizona has argued that the law simply complements federal law. Brewer has said that Arizona has borne the brunt of the federal government's failure to enforce current immigration laws, and that SB 1070 is an attempt to protect Arizona's citizenry against crime and costs she says are associated with illegal immigration. 

Sen. Chuck Schumer, D-N.Y., said on Tuesday during a Judiciary Committee hearing on the law that he would introduce legislation to block it even if the Supreme Court upholds it. Republican presidential hopeful Mitt Romney has previously said that the Justice Department should drop the lawsuit over SB 1070.

While the public sees the court case as a broad battle between state and federal interests, Wednesday's arguments will focus on an obscure point of law called implied preemption, said Dan Kowalski, a Texas immigration lawyer. Preemption is a legal doctrine that holds that certain matters are national in nature, and, therefore, federal law preempts state or local law.

According to Lyle Denniston of SCOTUSblog.com, Arizona has argued that federal immigration law does not directly bar states from passing legislation to help enforce those laws and also does not say that states have no role in immigration enforcement because it is solely the responsibility of federal authorities. 

If the federal government's role in immigration preempts Arizona's, it is implied. 

The federal government says that Arizona's law intrudes into federal enforcement and actually frustrated that enforcement, and that Congress has empowered the executive branch to make "sensitive judgments" about immigrants, according to Denniston. 

"All the justices know that it has these big implications, but at the same time they're trying to focus on this obscure point of law," Kowalski said. 

Outside the court, advocacy organizations of all stripes are focusing on the practical implications of the case. 

Immigrant-rights groups and others who oppose SB 1070 say that the law targets Latinos and encourages racial profiling. They worry that other states may move forward with similar legislation if the law isn't struck down in its entirety.

"Will there be one law or 50 laws across the country?" asked Richard Stolz, of Fair Immigration Reform Movement, an immigrant-rights group based in Washington. Stolz said he's worried that immigrants and their families, who in some cases are U.S. citizens, will suffer significant hardships if the bill is allowed to stand.

"The particular purpose of the Arizona law is to create as much suffering and fear in immigrant communities as possible to make people self-deport," he said.  

The state is seeking to reduce illegal immigration through the enforcement of the law, a process referred to as "attrition through enforcement."

SB 1070 supporters argue that states are forced to pass their own laws regarding illegal immigration because the federal government has failed to. 

"If you enforce laws against illegal immigration, then illegal immigrants will lack the opportunities that draw them here, like jobs that displace native workers and using taxpayer-funded resources," said Kristen Williamson, a spokeswoman for the Federation for American Immigration Reform. 

Despite the ideological chasm in the debate, there is some agreement. Both sides believe that the current immigration system is broken and want Congress to do something about it.

On Wednesday, FIRM and FAIR will share common ground; both plan to be on the steps of the Supreme Court to make their voices heard.

This article is from the archive of our partner National Journal.

This article is part of our Next America: Communities project, which is supported by a grant from Emerson Collective.

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