Department of Homeland Security Secretary Alejandro Mayorkas issued a memo Tuesday officially terminating the Trump administration's "Remain in Mexico" program.

Why it matters: The program, known formally as Migrant Protection Protocols (MPP), forced tens of thousands of asylum seekers to await their immigration court proceedings in often dangerous and squalid conditions in Mexico.

• DHS said approximately 68,000 people were returned to Mexico following their enrollment in MPP.

Context: President Biden issued an executive order in February to pause the program, and began allowing asylum seekers to enter the U.S. in phases.

• Biden ordered DHS to "promptly review and determine whether to terminate or modify the program."
• DHS said that between between Feb. 19 and May 25, approximately 11,200 people were allowed into the U.S. to wait for their hearings as part of the first phase of the rollback of MPP.
• DHS said it is still processing asylum seekers in phases.

What they're saying: "I have determined that MPP does not adequately or sustainably enhance border management in such a way as to justify the program’s extensive operational burdens and other shortfalls," Mayorkas wrote in the memo to the leaders of the Customs and Border Protection, the Immigration and Customs Enforcement Agency and Citizenship and Immigration Services.

• "Moreover, in making my assessment, I share the belief that we can only manage migration in an effective, responsible, and durable manner if we approach the issue comprehensively, looking well beyond our own border," the secretary added.
• "As immigration courts designated to hear MPP cases were closed for public health reasons between March 2020 and April 2021, DHS spent millions of dollars each month to maintain facilities incapable of serving their intended purpose."
• "Throughout this time, of course, tens of thousands of MPP enrollees were living with uncertainty in Mexico as court hearings were postponed indefinitely. As a result, any benefits the program may have offered are now far outweighed by the challenges, risks, and costs that it presents."

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