Federal judge halts Obama policy of detaining Central American mothers and children seeking asylum

FILE - In this June 25, 2014 photo shows a group of immigrants from Honduras and El Salvador who crossed the U.S.-Mexico border illegally are stopped in Granjeno, Texas. The influx at the border is largely families with children or by minors traveling alone. From October 2012 through the end of September 2013, the U.S. Border Patrol apprehended about 24,000 unaccompanied children. But between October and the end of June 2014, the number shot up to 57,000. Secretary of Homeland Security Jeh Johnson testified recently that the number is accelerating so fast that it could reach 90,000 by the end of September. Most of them are coming from El Salvador, Honduras and Guatemala. (AP Photo/Eric Gay, File) (AP)

MCALLEN, TX - SEPTEMBER 08: Families of Central American immigrants turn themselves in to U.S. Border Patrol agents after crossing the Rio Grande River from Mexico on September 8, 2014 to McAllen, Texas. Although the numbers of such immigrant families and unaccompanied minors have decreased from a springtime high, thousands continue to cross in the border illegally into the United States. The Rio Grande Valley sector is the busiest area for illegal border crossings, especially for Central Americans, into the U.S. (Photo by John Moore/Getty Images) (2014 Getty Images)

A federal court judge has issued a preliminary injunction against Immigration and Customs Enforcement's policy of detaining Central American mothers and children seeking asylum in the U.S.

The American Civil Liberties Union, which filed the case, claimed the detentions were part of a strategy to deter other asylum-seekers from coming to the U.S.

In granting the injunction, Judge James Boasberg of the U.S. District Court for the District of Columbia wrote that the Obama administration's "current policy of considering deterrence is likely unlawful, and ... causes irreparable harm to mothers and children seeking asylum."

Judy Rabinovitz, deputy director of the ACLU's Immigrants' Rights Project, said, ""The court held that it was illegal to detain families based on deterrence. It made clear that the government cannot deprive individuals of their liberty merely to send a message to others."

Proponents of taking tough action on the influx of Central Americans -- many of them unaccompanied minors -- who came over the border last year said that a weak U.S. response would encourage more illegal immigration.

In a statement about the court's Friday move, the ACLU said it had filed the case "on behalf of mothers and children who have fled extreme violence, death threats, rape, and persecution in Central America and come to the U.S. for safety."

"In rejecting the U.S. government's argument that detention of the women and children was necessary to prevent a mass influx that would threaten national security," the ACLU said, "the court wrote that the 'incantation of the magic word 'national security' without further substantiation is simply not enough to justify significant deprivations of liberty.'"

The Associated Press contributed to this report.