A federal judge issued a temporary order Friday allowing Texas to continue rejecting an ID commonly used by undocumented immigrants when seeking birth certificates for their U.S.-born children, NPR reported over the weekend.

According to the order, Texas can maintain its policy of refusing to accept matriculas — a form of IDs issued from Mexican consulates that are popular among undocumented immigrants — as the case proceeds. However, the judge — Austin-based District Judge Robert Pitman — said he was “troubled” by the fact that children of undocumented immigrants were not being issued a birth certificate, as “a birth certificate is a vital and important document” and the challengers had raised “grave concerns.”

The Texas policy of refusing matriculas dates back to 2008, officials say. However, the undocumented parents who brought the suit say the state only cracked down on the ID policy in recent years. They claim that not being able to obtain birth certificates for their children has made their kids second-class citizens, as it is required for everything from baptisms to school enrollment.

The parents are suing the state on the basis of the 14th Amendment’s birthright citizenship guarantee, the equal protection clause of the Constitution, and the Supremacy Clause, which says federal law on immigration and citizenship trumps state policy.

The state has cited security concerns with accepting matriculas. But Mexico, in a friend of the court brief supporting the undocumented parents, argued the ID cards issued by consulates are even more secure than the other IDs accepted for birth certificates.

Nevertheless, the judge said that “Texas has a clear interest in protecting access” to birth certificates and that challengers had so far not presented evidence that the state was acting “improperly” in excluding the matriculas:

“In summary, although the Plaintiffs have provided evidence which raises grave concerns regarding the treatment of citizen children born to immigrant parents,” the judge ruled, “this case requires additional determinations which can be made only upon development and presentation of an evidentiary record which thoroughly explores the facts and circumstances of the issues raised in this case.”