Supreme Court to hear arguments on Biden's bid to end Trump's 'Remain in Mexico' policy

The Supreme Court on Tuesday will hear oral arguments about the Biden administration's latest attempt to end a Trump-era immigration policy that's been upheld by multiple courts, but decried by human rights groups.

The "Remain in Mexico" policy, formally known as the Migrant Protection Protocols or MPP, required some asylum seekers arriving at the U.S. southern border to be sent back to Mexico while their immigration proceedings played out.

The program went into effect in 2019 under then-President Donald Trump's administration. By the end of Trump's term in office, the policy was used to send nearly 70,000 people back to Mexico. Groups such as Human Rights Watch say the policy violates migrants' rights and subjects them to a litany of dangers and abuses.

President Joe Biden suspended the program on his first day in office and tried to end it completely last year. But the administration's efforts were challenged by attorneys general in Texas and Missouri, and a federal judge in Texas ordered that the policy be reinstated.

A federal appeals court, and then the Supreme Court, declined the administration's efforts to pause the Texas court's ruling last August.

In October, Department of Homeland Security Secretary Alejandro Mayorkas issued a memo rescinding the Remain in Mexico policy once again. In December, the administration restarted it in accordance with the court's order, even as the White House lamented that it is "not our preference to be reimplementing" the policy.