El Paso, Texas — Illegal crossings along the U.S.-Mexico border in May are down by more than 50% compared to the record highs reported in December, giving the Biden administration an unexpected reprieve during a time when migration has historically surged, according to internal government data obtained by CBS News.

During the first 21 days of May, U.S. Border Patrol agents recorded a daily average of approximately 3,700 apprehensions of migrants between official ports of entry. That represents a 54% decrease from the 8,000 daily average in December, when illegal entries soared to a quarter of a million, an all-time high.

May is also on track to see the third consecutive month-over-month drop in unlawful border crossings, the preliminary U.S. Department of Homeland Security statistics show. In March and April, illegal crossings along the southern border dropped to 137,000 and 129,000, respectively, according to public government data. If the trend continues, Border Patrol is on pace to record between 110,000 and 120,000 apprehensions in May.

Border Patrol apprehensions don't include the number of migrants processed at official border crossings, where the Biden administration is admitting roughly 1,500 asylum-seekers on a daily basis.

While still elevated compared to pre-pandemic levels, the drop in migration this year has been unusual, bucking the trend in recent years of migrant crossings soaring in the spring. Senior U.S. officials have partially attributed the lower-than-expected levels of unlawful crossings to an aggressive crackdown on U.S.-bound migrants by the Mexican government.

Mayorkas on the border

In an interview with CBS News in El Paso on Thursday, Homeland Security Secretary Alejandro Mayorkas also credited Biden administration efforts for the downward trend.

"We have driven down the number of encounters at our southern border rather dramatically," Mayorkas told CBS News.

Mayorkas cited a "number of actions that we have taken, not only strengthening our enforcement, not only attacking the smugglers, but also building lawful pathways that enable people who qualify for relief to reach the United States in a safe, orderly and legal way."

The sustained drop in migrant crossings is welcome news politically for President Biden, who has faced withering criticism from two directions: Republicans and moderate Democrats who believe his immigration agenda is too lenient, and progressives who argue his administration has embraced some Trump-era border policies. Immigration has also emerged as a top concern for American voters ahead of November's presidential election.

Aware of the politics around immigration ahead of his election bid, Mr. Biden is considering an executive order that would attempt to suspend asylum processing along the southern border when illegal crossings spike, three people familiar with the White House's planning told CBS News. Officials are aiming to move forward with the move, which would rely on a broad presidential authority known as 212(f), in June, though the timeframe could shift, the sources said, requesting anonymity to discuss internal deliberations.

While he did not confirm the expected executive action, Mayorkas said he was "not ruling out options." 

"We look at options … every day, to see what more we can do to strengthen our border security in keeping with the law and our country's values," Mayorkas said.

Administration officials have frequently urged Congress to reform the U.S. immigration system, warning that any executive action could be held up in court because of legal challenges.

Senate Democrats tried and failed to advance a bipartisan border security bill for a second time on Thursday, calling the vote to highlight Republicans' opposition to the legislation in an attempt to shift public opinion on the issue.

That proposal, which was brokered by the White House and a small bipartisan group of senators earlier this year, would give the president an emergency power to shut down asylum between ports of entry when illegal border crossings soar to certain levels. It would also preserve asylum processing at official ports of entry, and allow migrants who pass their initial asylum interviews to work in the U.S. immediately after being released from federal custody. 

Most Republicans, including former President Donald Trump, have rejected the border agreement, portraying it as insufficiently strict.

Mayorkas on Thursday said he was "very disappointed" by the rejection of the border deal.

"I think President Biden said it quite crisply," Mayorkas said. "Some want the problem for political reasons, rather than deliver[ing] the solutions that border security and our country's security needs and the American people deserve."

Camilo Montoya-Galvez

Camilo Montoya-Galvez is the immigration reporter at CBS News. Based in Washington, he covers immigration policy and politics.

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