South Carolina's new immigration law won't take effect until January, but already the federal government and the ACLU are taking aim at it.

The U.S. Department of Justice is reviewing immigration-related laws that were passed in South Carolina, Utah, Indiana and Georgia, department spokeswoman Xochitl Hinojosa said Thursday.

"To the extent we find state laws that interfere with the federal government's enforcement of immigration law, we are prepared to bring suit," she said.

South Carolina's new law would require police to call federal immigration officials if someone is suspected of being in the country illegally. State and local law enforcement also would check a person's immigration status if they suspected that the person was not here legally.

S.C. Attorney General Alan Wilson, a Republican, said he is prepared for any legal challenge.

"I absolutely think this law is constitutional and absolutely think South Carolina would win," he said. "This is not in contrast to the federal law. ... This is in support of the law. It absolutely puzzles me that the federal government doesn't want help."

Gov. Nikki Haley indicated that she would regret seeing the Justice Department sue the state over the law.

"It's a sad day when the same federal government that won't do its job securing the border and enforcing America's immigration laws sues a state for implementing and enforcing ours," Haley spokesman Rob Godfrey said.

The new state law tightens what already were some of the nation's toughest measures to curb illegal immigrants living and working here, including a 2008 law aimed at stopping employers from using illegal labor.

The prospect of a legal challenge is welcome news to Diana Salazar, president of the Latino Association of Charleston, who is concerned about new laws cracking down on recent immigrants.

"My concern is if this continues, this might provoke negativity within the Latino community, and this is something people have not looked at," she said.

Victoria Middleton, executive director of the S.C. chapter of the American Civil Liberties Union, said her agency also intends to file a lawsuit.

"I can't be more specific right now," she added. "But (the planned suit) is for the same reasons we advocated against its passage. We think it will encourage racial profiling and discrimination."

Some say the Justice Department's actions challenging state immigration laws mark a stark change in its way of doing things. More often, the department files briefs or tries to take sides in a lawsuit filed by others.

Jonathan Turley, a constitutional law expert at George Washington University Law School, told The Washington Post, "I don't recall any time in history that the Justice Department has so aggressively challenged state laws."

The legal fighting began when Arizona passed a law last year requiring police to check immigration status if they stop someone while enforcing other laws. The department's suit prompted federal courts to block the most controversial aspects of the Arizona law.

State Sen. Chip Campsen, R-Isle of Palms, said in the big picture, the Justice Department's legal actions puts federalism at risk.

"State sovereignty is being encroached upon by this administration," he said. "What the public wants is less federal government involved in their lives, and the Obama administration is heading down the other path."

Catherine Templeton, who runs the state Department of Labor, Licensing and Regulation, said she is not worried about any potential lawsuit.

Her agency enforces a law that requires employers to check potential workers' immigration status using the federal E-Verify system.

"I hand-held that immigration law through the General Assembly with one and only one direction, which is to make sure this is constitutional," she said. "I am 100 percent confident that any challenge from the Obama administration or anyone else would fail.

"They could sue us all day long and waste everyone's resources."