A Fort Worth same-sex couple filed a federal lawsuit Tuesday claiming they were denied the opportunity to become foster parents to a refugee child because their relationship does not “mirror the holy family."

Fatma Marouf and Bryn Esplin, legally married nearly three years ago, contacted a Fort Worth-based affiliate of the U.S. Conference of Catholic Bishops. The U.S. Department of Health and Human Services contracts USCCB to coordinate some of its federal child welfare services. But, when Marouf, a professor of law and director of Texas A&M’s Immigrant Rights Clinic reached a representative by phone for their first interview, she says they were told sorry, you can't be foster parents because you don't "mirror the holy family."

"We were both completely shocked,” Marouf said. “I think we just looked at each other and then I wanted to clarify what they meant by that."

Marouf says she asked for that clarification – whether their same-sex marriage was the reason they were being denied.

"And then she said yeah then you're not eligible,” Marouf said of the phone interviewer.

"It was hurtful in realizing there was no overcoming that barrier,” said Bryn Esplin, an assistant professor of bioethics at the Texas A&M College of Medicine.

So Tuesday, with the help of the Lambda Legal defense organization, they filed a federal lawsuit against the Department of Health and Human Services and the United States Conference of Catholic Bishops and several other involved federal organizations. Federal taxpayer dollars are used for the Catholic charity to operate the foster and adoption program.

"The U.S. government is endorsing one set of religious beliefs over another in violation of the constitution and is unlawfully discriminating against LGBT people,” said Jamie Gliksberg, a staff attorney for Lambda Legal.

In the lawsuit the couple also says they asked if, perhaps, any of the children in the program might be lesbian or gay. They say they were told that "none" of the 700 children are LGBT.

"This is a serious and unconstitutional misuse of your federal taxpayer dollars and it needs to stop,” said Gliksberg.

WFAA has not yet received a response to the lawsuit from either Health and Human Services or the Conference of Catholic Bishops. Bryn Esplin and Fatma Marouf hope they answer they get by filing the lawsuit is at least a reversal of opinion, and a change of heart.