U.S. Supreme Court justices on Monday decided not to revive parts of Alabama’s strict anti-illegal immigration law.

The law, described as the strictest state-level measure on immigration, makes it a crime to harbor or transport undocumented immigrants, among other things.

In declining to consider the case, the Supreme Court upheld a federal appeals court ruling that blocked parts of the law.

Sam Brooke, an attorney for the Montgomery-based Southern Poverty Law Center, says lower courts have already said immigration reform is a function of the federal government and not the states.

The Obama administration last year asked the U.S. Court of Appeals for the 11th Circuit to block the law because immigration was a federal matter.

Proponents of the Alabama law argue that the federal government has been negligent in its duty to control immigration, forcing states to take the matter into their own hands.

Brooke says he hopes the ruling will motivate Congress to seek meaningful immigration reform. Both the U.S. Senate and the U.S. House of Representatives are considering bills that would overhaul immigration laws. 

A bipartisan group in the Senate has introduced a nearly 900-page bill that tightens enforcement, expands guest worker visas and offers a pathway to legal status for undocumented immigrants. A bipartisan group in the House is introducing reform bills in a piecemeal fashion, saying that they’re more likely to pass than a massive, single measure.

In the Supreme Court, Justice Antonin Scalia voted to hear the Alabama appeal.

A spokeswoman for Attorney General Luther Strange, Joy Patterson, says Scalia's vote is a sign that once additional courts have considered the issue, the Supreme Court will grant review.

Immigration advocacy groups lauded the Supreme Court’s decision not to take up the Alabama appeal.

“This ruling today is yet another important victory for comprehensive immigration reform,” said Janet Murguía, President and CEO of National Council of La Raza, a Latino civil rights group. “The Justices have rightly ruled that immigration policy must be set by the federal government."

The Associated Press contributed to this report.

Elizabeth Llorente is Senior Reporter for FoxNews.com, and can be reached at Elizabeth.Llorente@Foxnews.com. Follow her on https://twitter.com/Liz_Llorente