HOUSTON - Attorneys for the family of an undocumented Houston father just days away from deportation are trying an unusual last-minute legal tactic to allow him to stay in the United States.

On Monday in downtown Houston, lawyers filed a federal lawsuit arguing that deporting Juan Rodriguez would violate the religious beliefs of Rodriguez and his family; an approach they say has never been tried on an immigration case.

Family attorneys claim a deportation would violate the family’s Seventh-Day Adventist Christian beliefs, specifically a principle requiring families to stay together.

The legal team is banking on the Religious Freedom Restoration Act, a federal law that "ensures that interests in religious freedom are protected” and in 2014 was used to protect Hobby Lobby against some requirements of the Affordable Care Act.

Rodriguez has been in the United States illegally for more than a decade after fleeing violence in El Salvador. He had been allowed to stay and work legally in the U.S., if he checked in regularly with immigration officials.

Family members say Rodriguez did so 25 times without any issue, but at his last check-in in February, immigration officials told him he would be deported on June 29.

They allowed him to stay long enough to see his oldest of three daughters, Karen, graduate from high school.

“When the clock is ticking, when time’s running out, you learn how much your family means to you,” said Karen Rodriguez, 18, on Monday.

Attorneys for the family say Juan Rodriguez’s wife is unable to work because of health problems, and the family would likely have to go on public assistance.

Karen Rodriguez says the family would move to El Salvador if her father’s deportation goes through.

“If he goes, we go, and I’m willing to do it for my family,” she said, adding that her father pays taxes and has no criminal record.

Lawyers also say that because faith would compel Rodriguez’s wife and three daughters, who are all U.S. citizens, to follow him to El Salvador, the government would essentially be engaged in “de facto deportation” of their legal residents to one of the most violent countries in the world.

“(Criminals in El Salvador) are gonna see four American citizens coming back, they're gonna believe they have money,” said Rael Gonzalez, an immigration attorney. “And (Rodriguez and his family) don’t know this country. They don’t have any place to go to.”

KHOU 11 Legal Analyst Gerald Treece says the big question is whether a case like this one was what the U.S. Congress had in mind when they passed the Religious Freedom Restoration Act in 1993.

“It sounds like a valid argument until you think about it: Does it apply to everybody? Anybody’s religious group?” asked Treece. “It’s sort of a long shot, but it’s also the best shot they’ve got.”

When asked if a victory in this case would open the door for additional similar cases, Treece said it would “knock the door down”.

Rodriguez’s lawyers say they should know in the next several days whether a judge will try to stop the deportation at least temporarily.