Texas Attorney General Ken Paxton filed a proactive lawsuit on Monday on Senate Bill (SB) 4 with the U.S. District Court for the Western District of Texas. The State is preempting legal challenges from illegal alien advocacy groups by asking the court of a declaratory judgment to confirm the law is constitutional. SB 4 is set to take effect on September 1, 2017.

The Attorney General’s office filed the lawsuit just one day after Governor Gregg Abbott signed SB 4 into law. The lawsuit targets Travis County, Texas, and its Sheriff Sally Hernandez, who have been openly hostile to immigration enforcement and impose sanctuary policies upon the county, which includes Austin, the state capital. Even before its passage, illegal alien advocacy groups vowed to challenge the measure in court and put the brakes on it. A declaration from the court that SB 4 is legal, however, would limit groups’ ability to postpone implementation of the law by filing frivolous challenges.

Specifically, SB 4 prohibits state and local entities from adopting, enforcing, or endorsing policies that prohibit or materially limit the enforcement of immigration laws. Public university and college campuses are explicitly included in these requirements. SB 4 also authorizes law enforcement to inquire into a person’s immigration status during a lawful investigation to a criminal offense.

To ensure officers comply with the law, SB 4 subjects law enforcement officials with criminal, Class A misdemeanor, charges if they do not comply with detainers sent by the U.S. Department of Homeland Security. Additionally, localities or colleges that defiantly impose sanctuary policies may be subject to fines of between $1,000 and $25,500 per day the policy is in place.

“SB 4 is constitutional, lawful and a vital step in securing our borders,” Attorney General Ken Paxton said in a statement.

Since taking office, Governor Abbott’s administration has taken strong stands to limit the fiscal and safety costs of illegal immigration to Texans. Enacting anti-sanctuary legislation is a vital component to the governor’s immigration enforcement priorities.