The number of migrants unlawfully crossing the U.S. southern border has continued to drop markedly in July, nearing a threshold that would require officials to lift a partial ban on asylum claims enacted by President Biden, according to internal government data obtained by CBS News.

July is on track to see the fifth consecutive monthly drop in migrant apprehensions along the U.S.-Mexico border and the lowest level in illegal immigration there since the fall of 2020, during the Trump administration, the internal Department of Homeland Security (DHS) figures show.

In early June, President Biden invoked a far-reaching presidential authority to suspend the entry of most migrants entering the U.S. illegally, effectively shutting off access to the American asylum system outside of official ports of entry. 

Illegal border crossings — which were already falling before Mr. Biden's action — plunged further after the order took effect, reaching a three-year low in June.

But the DHS regulation implementing Mr. Biden's proclamation stipulated that the asylum crackdown would be lifted if the 7-day average of daily migrant apprehensions between ports of entry fell to 1,500.

In the past week, the average of daily illegal crossings counted in the regulation's calculations reached roughly 1,650, according to the internal DHS figures. Those calculations, as dictated by the regulation, exclude crossings by unaccompanied children who are not from Mexico. Those children are typically housed in government-run shelters until they turn 18 or are placed with a U.S.-based sponsor, as mandated by a 2008 anti-trafficking law.

If the 7-day average of daily illegal crossings dips to 1,500, the regulation says, Mr. Biden's asylum proclamation would be "discontinued 14 days after" Homeland Security Secretary Alejandro Mayorkas makes a "factual determination" about the threshold being reached.

"The Departments have determined that the 1,500-encounter threshold is a reasonable proxy for when the border security and immigration system is no longer over capacity and the measures adopted in this rule are not necessary to deal with such circumstances," the regulation says.

Asylum limits could remain in place

While illegal border crossings are nearing the 1,500 deactivation threshold, it's possible that they may remain above that number, keeping the partial asylum ban in place. And even if the 1,500 trigger is reached, Mr. Biden's proclamation would be reinstated if the 7-day average of daily illegal crossings were to rebound to 2,500. 

A senior U.S. Customs and Border Protection (CBP) official said the agency does not expect the partial ban on asylum requests to be deactivated imminently, noting that illegal crossings appear to be plateauing. 

"We're not in a place yet where we're a day … or days away from being below 1,500," the official told CBS News.

But the official acknowledged that reaching the 1,500 trigger is possible and confirmed there's been internal planning and preparations for that eventuality. 

If Mr. Biden's proclamation is suspended, the official said, CBP would still strive to place migrants in expedited deportation proceedings, instead of releasing them with notices to appear in immigration court. Another Biden administration asylum restriction that applies to those who don't seek refuge in third countries before crossing into the U.S. would also remain in place.

A dramatic change at the border 

With an overall average of roughly 1,800 daily migrant apprehensions so far in July, Border Patrol is on pace to record fewer than 60,000 migrant apprehensions this month, the lowest level since September 2020, according to unpublished DHS data. That average, unlike the one used in the asylum regulation's calculations, includes all unaccompanied children.

The current situation at the southern border represents a dramatic change from just late last year, when illegal crossings rose to a quarter of a million in December, an all-time monthly high. After that record-breaking influx, the Mexican government, at the request of U.S. officials, ramped up operations to stop migrants from reaching American soil.

Immigration experts credited the Mexican government's migration crackdown with playing a key role in the sustained drop in migrant crossings recorded by American officials this year. Temperatures in the southern U.S. have also soared in the summer, making the migration journey even more perilous.

But U.S. officials said Mr. Biden's move to partially shut down asylum processing has led to a more acute drop in unlawful crossings. Because it makes it easier for U.S. officials to deport more migrants, the proclamation has sharply reduced the releases that authorities view as a factor that encourages migration. 

Still, not everyone is being deported quickly. Some groups, such as unaccompanied children, medically vulnerable migrants and those who secure appointments to be processed at legal entry points, are exempt from the partial asylum ban. Some migrants who are disqualified from asylum under the policy are also still allowed to stay because the U.S. does not carry out regular deportations to their home countries due to diplomatic and logistical constraints.

Progressive advocacy groups have strongly decried Mr. Biden's asylum crackdown, and the American Civil Liberties Union is arguing in federal court that the policy violates U.S. and international refugee law. 

Theresa Cardinal Brown, a senior adviser at the Bipartisan Policy Center and a former government immigration official under Presidents George W. Bush and Barack Obama, said the legality of Mr. Biden's actions are "still an outstanding question." But she said the drop in releases under the policy is affecting migrants' decisions, at least in the short-term.

"When a sufficient number, it doesn't necessarily have to be everybody, but a sufficient number of people are not allowed to come in, to wait and succeed in coming in, that does send a signal back," she said.

In:
• Joe Biden

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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