A union representing U.S. asylum officers has denounced a Trump administration policy mandating that asylum-seekers wait in Mexico for their immigration hearings, warning Wednesday that the policy is risking migrant lives. According to The Washington Post, the labor union filed a brief supporting an ACLU lawsuit seeking to end the Migrant Protection Protocols program. In the filing, the union claimed its members—who are tasked to turn asylum-seekers away at the border—felt that the policy was “fundamentally contrary to the moral fabric of our Nation.” The policy has reportedly sent about 12,000 asylum-seekers back to Mexico since the beginning of this year. The Justice Department declined to comment on the filing to the Post, and the Department of Homeland Security reportedly did not respond to the newspaper’s requests for comment. Some of these asylum officers told Vox that they felt their jobs have become a “lip service” due to the policy. “I’m not adjudicating that case. It’s like someone else sticking their hand inside me, like a glove,” an officer told the website.