Federal appellate judges considering a legal challenge to the so-called "third country" asylum rule—Trump Administration rule changes that bar asylum for migrants who fail to apply for protection in a country they transit through to reach the U.S.—raised concerns about the lack of evidence that asylum seekers would be safe in applying for asylum in venues such as Mexico or Guatemala.

But the three-judge panel of the U.S. Court of Appeals for the Ninth Circuit, hearing arguments Monday over an injunction barring the rule's implementation, likewise raised concerns about the nationwide scope of the injunction issued earlier this year by U.S. District Judge Jon Tigar of the Northern District of California.

The appellate court considered Tigar's injunction blocking enforcement of the rule that Administration lawyers contend is directed at stemming the tide of Central American migrants coming to the country through Mexico. Justice Department lawyer Scott Stewart, representing the administration Monday, called the rule a "critical" executive branch effort to deal with "unconstrained mass migration" at the nation's southern border. The nation's asylum system, he said, puts a high level of discretion with the Attorney General to make the final call on when asylum should be granted, and the rule was aimed at weeding out those immigrants with less urgent claims.

But Judge Eric Miller of the U.S. Court of Appeals for the Ninth Circuit questioned whether issuing a categorical rule barring people who passed through Mexico without applying for asylum there had effectively rendered some asylum seekers with valid claims ineligible. "Where did you address the concern that Mexico is not really a safe place for people to apply?" asked Miller, a nominee of President Donald Trump who was confirmed to the Ninth Circuit earlier this year.

Justice Department lawyer Stewart pointed to the language of the rule itself, which led to further questioning later from Judge Richard Clifton of the U.S. Court of Appeals for the Ninth Circuit, who noted the rule didn't speak to the safety of the asylum seekers. Stewart told Clifton that safety is "not the primary point of the rule."

"It's the primary point of asylum," Clifton responded.

Still, Clifton and his colleagues questioned the nationwide scope of Tigar's injunction. Clifton called the nationwide damages claimed by the immigration advocacy organizations represented by the American Civil Liberties Union who are plaintiffs in the case "a thin soup," especially those related to training lawyers to handle asylum cases outside the Ninth Circuit.

In the district court below, Tigar issued a nationwide injunction in July finding that the rule was "inconsistent with the existing asylum laws" passed by Congress. After the Ninth Circuit earlier limited the injunction to the boundaries of the circuit, Tigar again extended it nationwide in September.

The U.S. Supreme Court later that month temporarily lifted the injunction and allowed the third-country asylum rule to go into place pending the outcome of the government's Ninth Circuit appeal or Supreme Court review, if a petition is filed following any forthcoming Ninth Circuit decision. The high court granted the government's request for a stay without explanation. Justices Ruth Bader Ginsburg and Sonia Sotomayor dissented, with Sotomayor writing that "although the stakes for asylum seekers could not be higher—the Government implemented its rule without first providing the public notice and inviting the public input generally required by law."

At the argument Monday, Clifton noted that the posture of the case illustrated that nationwide injunctions could be a "two-edged sword." Even if the court were to side with the plaintiffs, he noted, its ruling wouldn't even affect the Ninth Circuit until the Supreme Court weighs in. 

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