March 31, 2013 -- A German family that fled to the United States in 2008 to be free to homeschool their children is fighting deportation after a decision granting them asylum was overturned.

Uwe and Hannelore Romeike, devout Christians from the southwest of Germany who now have six children, initially took their three oldest children out of school in their native country in 2006. Shortly after, the German government started fining the family and threatening them with legal action.

Home schooling has been illegal in Germany since 1918, when school attendance was made compulsory, and parents who choose to homeschool anyway face financial penalties and legal consequences, including the potential loss of custody of their children.

To escape such legal action, the family fled to the United States in 2008 and was granted political asylum in 2010, eventually making their home in Tennessee. U.S. law states that individuals can qualify for asylum if they can prove they are being persecuted because of their religion or because they are members of a particular "social group."

U.S. Immigration and Customs Enforcement challenged the decision to grant the Romeikes asylum to the Board of Immigration Appeals in 2012, claiming that Germany's stringent policy against homeschooling did not constitute persecution.

The board overturned the initial asylum decision, arguing that homeschoolers are not a particular social group because they don't meet certain legal standards, The board said that the home-schooled population is too vague and amorphous to constitute a social group.

Now the family is fighting that decision in the Sixth Circuit Court of Appeals, which will hear the case on April 23.

"We think we have a pretty strong case," Romeike family attorney Michael Donnelly told ABC News. "We feel that what Germany is doing by preventing this family and a lot of other families from exercising their rights in the education of their children violates a fundamental human right," he said.

Donnelly says the right of parents to decide the direction of their child's education has been established in Article 26, section 3 of the United Nations' Universal Declaration of Human Rights which reads: "Parents have a prior right to choose the kind of education that shall be given to their children."

"Our Supreme Court has said that the state cannot unduly burden, restrict, or direct childrens' education privately," said Donnelly, referring to a precedent established in a 1925 case, Pierce v. Society of Sisters.

Karla McKanders, an asylum and refugee law specialist at the University of Tennessee at Knoxville, told ABC News the family faces an uphill battle.

"They are trying to establish that they are eligible for asylum under the social group category, which is a difficult group to prove in the first place," McKanders said.

McKanders also says that public policy implications as far as the United States' relationship with Germany could also be in play in this case, and that immigration officials may be wary of setting a precedent that establishes homeschooling as a means for asylum.

"They don't want to open up the floodgates for similar asylum claims based on these grounds," she said.

Recent changes in immigration enforcement policy are also at issue.

In 2011 the Obama administration initiated a new policy called "prosecutorial discretion" that gives the government broad power to pursue only high-priority cases. The policy was designed to give Department of Homeland Security the power to decide which deportation proceedings it wishes to pursue.

"This case would probably fall under one of those cases that should be a low priority because you have a family that is fleeing based on their own beliefs," McKanders said. "They of course do not have a criminal background so it should be one of those cases where they are not spending a lot of resrouces, but it's not."

"The attorney general has the authority at any point in time to grant the family asylum," said Donnelly, who added that he hopes that's eventually what happens in this case. "These folks should be allowed to stay, they meet the standard."

The Justice Department declined to comment to ABC News. Immigrations and Customs Enforcement said it is its policy not to comment on pending litigation in federal court.

Donnelly and Home School Legal Defense Association leader Michael Farris have petitioned the White House to allow the Romeike family to remain in the country.

"Every state in the United States of America recognizes the right to homeschool, and the U.S. has the world's largest and most vibrant homeschool community," read the formal petition on the White House website.

"Regretablly, this family faces deportation in spite of the persecution they will suffer in Germany. The Romeikes hope for the same freedom our forefathers sought," it read.