Nick Miroff, Washington Post, June 18, 2019

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U.S. authorities detained more than 85,000 “family unit” members at the border in May, an average of nearly 2,800 per day. That number has declined about 13% since the beginning of June, a period during which Trump threatened to impose tariffs on Mexico and the government of President Andrés Manuel López Obrador agreed to an immigration crackdown to avoid the penalty.

Overall, U.S. officials say they are expecting a 15-20% decline in border arrests from May, when authorities detained more than 144,000 and migration levels reached their highest point since 2006. {snip}

Since the June 7 immigration deal with Trump, Mexico has begun to deploy thousands of national guard forces to set up highway checkpoints and catch more Central American migrants as they head northward toward the U.S. border. The United States also has begun to send more asylum seekers back across the border into Mexico to await their U.S. immigration court hearings, an expansion of the Migrant Protection Protocols program that prevents the migrants from staying in the United States while they go through the asylum process.

The Mexican immigration enforcement crackdown has been concentrated in southern Mexico, so U.S. officials say it could take several weeks for the full effect of the effort to show up as a reduction in crossings at the U.S.-Mexico border. As the United States turns more people away to Mexico during the asylum process, authorities hope it will act as a deterrent.

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Border arrests typically surge in the spring, when demand for U.S. farm labor grows, then subside during peak summer months. Border arrests declined 17% from May 2018 to June 2018, an indication that the expected decline this month could follow that same trend.

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If the June arrest numbers continue to decline, it would be the first month this year that Customs and Border Protection has recorded a decrease in enforcement actions.

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The Mexican government did not commit to a specific, numerical enforcement goal during the negotiations, a senior Mexican official said Monday. But Mexico has assured the United States that its enforcement efforts will deliver the major reductions in migration levels Trump is demanding.

The United States, via the MPP program, has been sending about 250 asylum seekers back to Mexico per day, but U.S. officials plan to increase that to at least 1,000 per day in coming weeks.

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