A federal judge in Philadelphia on Tuesday rejected a request by dozens of undocumented immigrant mothers and children to declare part of the asylum process unconstitutional, a step that clears the way for their deportation to Central America.

In a case that advocates say could end up before the Supreme Court, U.S. District Judge Paul S. Diamond declared that the expedited review process that led to their expulsions was not unconstitutional and that such removal decisions are an executive branch prerogative not subject to federal court oversight.

Diamond then lifted the orders that have blocked the expulsion of the 29 women and their 35 minor children.

The plaintiffs, all current and former detainees at the U.S. Immigration and Customs Enforcement-supervised family-detention facility in Berks County, claimed they came to this country to flee gang violence in Guatemala, Honduras, and El Salvador.

They made their cases in expedited-asylum proceedings before an immigration agent, who then decided if they deserved a fuller hearing in Immigration Court.

At the heart of the process is the "credible fear" interview, in which the women all spoke of their fears of "persecution" or "torture" if they were forced to return to the countries they fled.

Anyone who clears the credible-fear hurdle is supposed to be withdrawn from the expedited removal process and given extended consideration of an asylum application. In this case, none of the plaintiffs was deemed to have a credible fear.

So with the help of ACLU lawyers and others, they argued that the process unfairly sealed their fates because they did not have adequate time to prepare for their interviews.

The case drew briefs from interest groups on both sides of the debate about illegal immigration.

Supporters of the women say deportation will subject them to "terrible abuse."

Government attorneys contend the expedited removal proceedings, which occur quickly after a person has crossed the border, and generally happen without counsel, are constitutional. Diamond agreed.

"Congress has determined that expedited removal decisions - particularly the evaluation of credible-fear claims - are best left to the executive, not the courts," he wrote in his 31-page opinion.

"Because we are a nation of immigrants, it is vital, especially for those of us who are the children of immigrants, to ensure integrity and fairness in the immigration process. All the good will in the world, however, cannot alter the judiciary's necessarily limited role in the admissions process."

Diamond stayed his order for 14 days to give the plaintiffs time to appeal.

Lead counsel for the women and children, Lee Gelernt of the American Civil Liberties Union's national Immigrant's Right Project, said: "We believe [Diamond's] decision is wrong."

Diamond wrote that the plaintiffs "argue mistakenly that expedited removal proceedings are akin to ... deportation proceedings," but the "procedures governing exclusion and those governing deportation are subject to different constitutional requirements."

A person who loses the right to reside in the United States has "a number of substantive rights not available" to a person who is denied admission in an exclusion proceeding, he wrote.

"That is the crux of his opinion, which we think is wrong," said Gelernt, whose chief argument hinges on the precedent of habeas corpus law.

"Noncitizens who have made an entry into the United States and are arrested have always been treated as deportable for constitutional purposes and not as people seeking entry. ... That is bedrock law going back more than a century. We are not aware of any precedent depriving people of their habeas corpus rights once they are inside the country."

Absent a stipulation by the government to allow a voluntary stay, he said, he will file an appeal.

He said he intends to visit the clients Wednesday at the Berks detention center to brief them.