Texas AG announces probe into Dallas over its sanctuary polices: 'The law is not optional'

On Thursday, Paxton announced the investigation, as well as a formal request for city and Dallas Police Department records concerning the police department's refusal to comply with state and federal immigration laws. 

"My office will take all necessary legal actions to ensure compliance with state law and hold accountable any local entity that defies its legal obligations," he added.

Paxton's office has requested all policies, training materials and communications related to Dallas' enforcement or non-enforcement of immigration laws, including any records reflecting decisions to decline cooperation with federal immigration authorities.

Paxton said the chief's remarks "raise serious concerns" that the city and police department are possibly violating Texas law, which prohibits local entities from adopting sanctuary city policies that limit immigration enforcement.

In a statement to Fox News Digital, the city of Dallas said: "We are reviewing the letter received from the Texas Attorney General's Office and will respond at the appropriate time."