WASHINGTON -- The Supreme Court on Thursday said the Biden administration can end a Trump-era immigration policy known as "Remain in Mexico" that had forced thousands of asylum seekers to wait south of the border while their claims were adjudicated.
The court ruled 5-4, with Chief Justice John Roberts and Justice Brett Kavanaugh joining the three liberal justices in the majority.
Officially termed the "Migrant Protection Protocols" -- or MPP -- the policy was created in 2019 to send unauthorized immigrants, including asylum seekers, back to Mexico while their cases are processed in immigration court.
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Trump administration officials intended the policy to serve as a deterrent against flows of migrants along the southwest border. Human rights observers and immigrant advocacy organizations said the policy contravened international law, putting vulnerable people at risk of higher documented rates of kidnapping, extortion and violence in the areas they were forced to wait.
President Biden attempted to formally end the MPP last year but was sued by Republican-led states Texas and Missouri, which alleged the Immigration and Naturalization Act required the administration to continue the program. A federal court ordered the policy to continue as legal challenges played out.
The INA says that the Department of Homeland Security "shall" detain unauthorized noncitizens pending immigration proceedings, but it also allows for their parole inside the country on a case-by-case basis if it's determined to be for "public benefit."
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Congress has never allocated sufficient resources to fulfill the law's requirement of detaining all migrants and asylum seekers pending an immigration hearing; every administration has had to exercise some level of discretion in enforcement.
The Biden administration argued that the MPP required costly and complicated negotiations with Mexico and that foreign policy authority rests solely with the president - not the states or federal courts.
Under President Donald Trump, roughly 70,000 migrants were enrolled in the program and sent back to Mexico to await immigration hearings in the U.S. So far, the Biden administration has enrolled 5,000 migrants in the program. Just 2.4% have been granted relief after their claims were heard, one recent study found.
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The court's decision comes as the flow of migrants to the southwest border continues to strain law enforcement and humanitarian resources. Customs and Border Protection reported 239,416 encounters with migrants in May, a two percent increase compared to April; a quarter of those were repeat offenders.
A separate Trump-era border enforcement policy known as Title 42 -- activated during the pandemic to rapidly expel migrants due to COVID -- remains in effect and unaffected by the court ruling. Biden has also tried to rescind Title 42, but lower courts have ordered it continued as legal challenges proceed.
This is a developing story. Please check back for updates.