SAN ANTONIO - Senate Bill 4 has been the topic of much debate across the state. Cities like San Antonio joined in on a lawsuit, in hopes of stopping it from being enforced.

A preliminary hearing is set for Monday at the Federal Courthouse in downtown San Antonio where every major city in the state along, with San Antonio, will be challenging the state's anti-sanctuary city law.

The law is supposed to take effect in September and allows police to ask anyone they detain about their immigration status, not just during an arrest.

Last week, Houston joined several cities including San Antonio, Austin, and Dallas in trying to stop it from taking effect.

On Friday, the law got the full backing of the Trump administration with Attorney General Jeff Sessions writing that Texas has followed the lead of President Donald Trump's tougher stance on illegal immigration.

Monday morning, multiple groups plan to rally outside the courthouse all day. These groups believe the bill opens the door to racial profiling. They expect at least 400 people on the steps of the federal courthouse.