The judge found a likelihood that the law used to implement the program does not apply to the 11 asylum-seekers who sued, plus, it does not offer enough protections to those who are returned. He noted, however, that his order doesn't address whether Congress could authorize such a program with more safeguards, or if it is a "wise, intelligent, or humane policy."
DHS appealed to the 9th U.S. Circuit Court of Appeals, which temporarily stayed the decision Friday until the court can be further briefed.
The legal fight comes after a federal judge in San Francisco blocked Trump's attempt to prevent migrants who crossed the border illegally from claiming asylum. The aim was to direct all asylum-seekers to the ports of entry, where caseflows can be metered.
But the judge said the policy was not in line with the law, which states migrants can seek asylum anywhere on U.S. soil.
The most visible piece of Trump's immigration agenda -- his border wall -- won one round in San Diego last year.
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A federal judge ruled the administration did not abuse its discretion in waiving environmental laws in its rush to begin building and replacing border barriers, including projects in San Diego and Calexico. Instead, the law gives wide authority to DHS when it comes to securing the border, he ruled.
The Center for Biological Diversity and California are appealing the ruling. Meanwhile, DHS continues to waive environmental reviews for wall projects elsewhere.
Another battle is brewing over Trump's declaration of a national emergency to secure funding for more construction. California and 19 other states are trying to block the president from diverting money from other areas -- including military construction projects and anti drug-trafficking programs -- to fund more wall.
Similar suits have also been filed by environmental groups, as well as Texas landowners.