SAN ANTONIO - It's a Texas-sized court fight to stop a new state law banning sanctuary cities.

That legal fight is happening inside a federal courtroom in downtown San Antonio pitting many Texas cities, including the Alamo City, against the state of Texas.

The fight over sanctuary cities is now before a judge.

MALDEF, the Mexican American Legal Defense and Educational Fund, says the law, known to most as SB4, violates the 1st, 4th and 14th amendments of the U.S. Constitution.

"We will argue today that SB4 is preempted by federal law and that it violates individual people's rights," said Nina Perales, the Vice President of Litigation for MALDEF.

While critics say the law paves the way for racial profiling, supporters stress this will only help keep criminals off the streets.

Texas Senator Charles Perry, the author of Senate Bill 4, released the following statement regarding Monday's federal hearing:

"The public understands that law enforcement officials should not help those found guilty of serious crimes, such as sexual assault and burglary, evade federal immigration detainers. This is why the majority of Texans support the bill I authored and passed banning sanctuary cities, despite misinformation and fear mongering surrounding the bill. The participation by President Trump's Department of Justice in today’s court hearing shows that Senate Bill 4 is not about taking on the federal immigration role, but only to partner with them to keep those who commit dangerous crimes off the streets. I am confident the court system will rule Texas' ban on sanctuary cities constitutional. I know that the Office of the Texas Attorney General will strongly defend this bill in court today and win."

Cameras were not allowed inside the federal courtroom where MALDEF, on behalf of San Antonio, and multiple immigrant advocacy groups fought to block SB4 from taking effect this September.

"What we hope will happen is that this case will send a very powerful message: In Texas, we should embrace diversity, not suppress it," Raul Reyes, Mayor of El Cenizo said.

The City of El Cenizo on the Texas-Mexico border holds the lead in the case in Monday's preliminary injunction hearing.

"I'm glad we have more cities. Every major city in Texas has stood up and said, 'We won't tolerate this in our community'," Reyes said. "No dollar sign is more valuable than doing the right thing."

SB4 will allow local law enforcement to ask about a person's immigration status during a traffic stop.

It will also allow the removal or persecution of elected officials who oppose SB4.

In the courtroom, when asked for his name, Judge Nelson Wolff responded to Attorney General Ken Paxton's lawyer, "Under your law, you may soon have to call me former Judge Wolff."

Wolff told state attorneys he'd be fine with being removed from office by not complying with SB4 if Governor Greg Abbott got removed from office for passing unconstitutional laws.

The state argues Sb4 broadens protections against racial profiling, saying it will protect more people.

Attorneys for Ken Paxton also say the law won't mean local officers will take on the role of ICE agents. It will instead help them keep criminals off the streets.

However, immigrants - undocumented or not - fear for their safety and their families.

"I live with lots of worries that one day when I get home, my mom or dad won't be there because they got taken away from me," said Wendy, 9, who spoke at a rally outside the federal courthouse.

Economy experts from Austin reported a 152 percent increase in school absences because of ICE raids.

"We have until September 1 to make our feelings known that local law enforcement and local elected officials will fight back against unconstitutional legislation," San Antonio Mayor, Ron Nirenberg said.

Attorneys for President Trump said ICE will not detain people unless someone is arrested.

MALDEF asked Councilman Rey Saldaña, who also took the stand Monday, if he believes San Antonio police will ask people for their papers if the law goes into effect.

His response was, "Unfortunately, yes."

No decision was made Monday. We expect a ruling from Judge Orlando Garcia very soon.