The moves, outlined in a pair of memos signed by DHS Secretary John Kelly, include an end to the policy of releasing people caught at the borders pending deportation hearings, hiring thousands more federal agents, sending more judges and officers to deal with asylum claims, enlisting more help from local police and speeding up removal proceedings for a larger number of people who are in the country illegally.
The memos also recommend authorities seek prosecution of parents who pay smugglers to bring their children into the United States — decisions that will ultimately be made by federal prosecutors.
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"The surge of illegal immigration at the southern border has overwhelmed federal agencies and resources and has created a significant national security vulnerability to the United States," Kelly wrote.
That, he said, includes a record backlog of 534,000 cases pending before immigration judges, and a soaring number of people taken into custody at the border with Mexico. Between the fall of 2015 and the fall of 2016, the number of monthly apprehensions increased by more than 10,000, he said.
With detention facilities currently unable to keep up with the numbers, Kelly said, officials should do what it can to expand them, and in the meantime prioritize people who are seen as most potentially dangerous or at risk of fleeing.
Kelly's memos emphasize the threat from drug trafficking organizations and street gangs made up of immigrants from south of the border.
His memos are nearly identical to executive orders signed by Trump last month as part of his campaign promise to take a harder line on illegal immigration. The memos add detail on how the new priorities will be carried out by U.S. Immigration and Customs Enforcement, U.S. Customs and Border Protection and U.S. Citizenship and Immigration Services. That includes the construction of a wall along the southern border.
These moves are separate from Trump's ban on travel from seven majority-Muslim countries, which is has been blocked by federal courts and could result in a newly written executive order this week.
The memos largely override previous orders from former President Obama.
But, significantly, the memos leave two orders in place: one concerning young people, known as "dreamers" who came to the U.S. as children but were allowed to stay and work under a program known as Deferred Action for Childhood Arrivals, or DACA. The second expands who would be eligible for DACA and allows parents to stay in the country if they came here illegally to join their U.S. citizen or permanent resident children.
The second, however, has been blocked in federal court.