A federal judge in Atlanta could decide the immediate fate of Georgia’s tough new anti-illegal immigration law today and trigger a chain of additional legal challenges that legal observers say could reach all the way to the U.S. Supreme Court.

U.S. District Judge Thomas Thrash has scheduled a 10 a.m. hearing for several civil and immigrant rights groups to make their case for halting Georgia’s law.

The American Civil Liberties Union, National Immigration Law Center and others argue the law is unconstitutional and are asking Thrash to put the law on hold pending the outcome of a lawsuit they have filed to block it.

Thrash is also planning to hear a request from Republican state Attorney General Sam Olens to dismiss the ACLU’s lawsuit. Olens’ office argues the state and U.S. constitutions grant Georgia immunity from such lawsuits.

Thrash, who was nominated to the court by President Bill Clinton, recently indicated he could immediately issue his decisions Monday after telling attorneys in the case that he has been known to rule from the bench.

Whoever loses after Monday’s hearings is expected to appeal to the 11thU.S. Circuit Court of Appeals in Atlanta. The case could eventually make its way to the U.S. Supreme Court along with other legal challenges targeting similar laws in Arizona and Utah, said R. Keegan Federal Jr., one of the attorneys who is seeking to halt Georgia’s law.

“I do fully expect this one to end up there” at the U.S. Supreme Court, said Federal, a former DeKalb County Superior Court judge. “But I don’t think it will end up there all by itself.”

State legislators who crafted the law argue it is constitutional and predict it will stand up in court. The law gives Georgia law enforcement the new authority in fighting illegal immigrants, including the power to detain suspected illegal immigrants  They said the state needed to act because the federal government has failed to seal the nation’s borders, letting illegal immigrants stream into Georgia, take jobs from U.S. citizens and burden its taxpayer-funded resources.

Other attorneys who are fighting Georgia’s law predict a lower court will rule in their favor and scrap the measure.

A spokesman for the state attorney general’s office declined to comment because the case is still pending. But Arizona Senate President Russell Pearce, the Republican architect of his state’s immigration enforcement law, also predicted the Supreme Court will decide the matter for all states.

Last year, a federal judge put some of the most controversial parts of Arizona's measure on hold after the Obama administration argued they interfere with the federal government's authority to set and enforce immigration policy. A federal appeals court recently upheld that judge's decision. Arizona’s governor has announced she is appealing to the U.S. Supreme Court.

Last month, a different federal judge halted a similar law in Utah, citing how it is similar to the Arizona legislation, also known as Senate Bill 1070. Alabama’s governor signed a tough law patterned after Arizona’s measure this month.

Pearce is predicting Arizona will prevail at the U.S. Supreme Court, arguing the case “is as much about states’ rights as anything else.”

“I believe SB 1070 will be heard by the U.S. Supreme Court and win,” Pearce said, “and that will pave the way for Alabama and Georgia and other states.”

Court officials in Atlanta are expecting a large turnout for today's hearing, so they reserved a second courtroom where a spillover crowd could watch the proceedings on closed-circuit television.

The Georgia law, which takes effect July 1, would empower local and state police to investigate the immigration status of certain suspects and arrest illegal immigrants and take them to state and federal jails. The plaintiffs argue this part of the law is unconstitutional because it invites racial profiling and could prolong ordinary police stops and authorize police to detain people for lengthy periods of time in violation of the Fourth Amendment, which guards against unreasonable searches and seizures.

The plaintiffs are also targeting a provision of the law that would punish people who -- while committing another crime -- knowingly transport or harbor illegal immigrants or encourage them to come to Georgia. The lawsuit says this part of the law intrudes on the federal government's power to regulate immigration.

In court papers filed Friday, the state attorney general’s office says the plaintiffs are assuming police will carry out the law unconstitutionally. Meanwhile, the state argues the new law will help protect illegal immigrants from crooked employers.

“While recognizing the substantial impact of illegal immigrants on Georgia’s economy, there is also a need to protect the illegal immigrant from abuses,” the state attorney general’s office says in a court brief. “By creating a legal mechanism where individuals who transport, harbor and entice illegal aliens into the state are punished and where employers are required to verify citizenship, Georgia protects these aliens from these abuses.”

Staff writer Bill Rankin contributed to this article.