A federal judge on Friday dismissed a lawsuit seeking to scrap a key part of Georgia’s sweeping anti-illegal immigration law.

The 2011 statute gives police the option of investigating certain suspects’ immigration status. It also empowers police to detain and jail people found to be in the country illegally.

U.S. District Judge Thomas Thrash placed Georgia’s law on hold in 2011 before it could go into effect, after civil and immigrant rights activists sued to block it. Critics say the statute is unconstitutional and could lead to racial profiling even though the statute explicitly prohibits that.

The state appealed to the U.S. 11th Circuit Court of Appeals in Atlanta, which reversed Thrash’s ruling in August. In December, Thrash signed an order complying with the appeals court’s decision, lifting the preliminary injunction he had issued against the law.

The plaintiffs were seeking to gather evidence to determine whether authorities are violating people’s constitutional rights by carrying out the law. But on Friday, Thrash granted Gov. Nathan Deal and Attorney General Sam Olens’ request to dismiss their complaint.

Thrash said the plaintiffs cannot meet their burden of showing the law could never be applied constitutionally. Yet, he indicated his decision does not prevent groups from filing separate lawsuits challenging the statute.

In March, Thrash permanently blocked Georgia from enforcing a separate law that would punish people who – while committing another crime – knowingly transport or harbor illegal immigrants or encourage them to come to Georgia. The same civil and immigrant rights groups sued to block that law, arguing it is unconstitutional. The 11th Circuit Court of Appeals in Atlanta supported Thrash’s position, ruling the statute is pre-empted by federal law.