Police officers guard a bus of deportees near the international bridge in Reynosa, Mexico, on Dec. 12. (Kevin Sieff/The Washington Post)

In a series of tweets Thursday, President Trump sought to justify his calls for a wall along the U.S. border with Mexico by pointing to the rising murder rate in that country.

In doing so, however, he also highlighted the dangers of the Trump administration’s new “remain in Mexico” asylum policy, which requires those who have applied for asylum at the U.S.-Mexico border to return to Mexico for months while they await a decision.

Trump’s tweets noted that there were 33,341 murders in Mexico in 2018, a rise he attributed to the drug trade.

Trump’s appeared to reference figures released by Mexico’s Interior Ministry this month. There are other estimates that suggest the number might be lower, but even those are worryingly high: Mexico’s public safety secretariat estimated there were 28,816 homicide cases opened in 2018 — a 15 percent increase over the previous year.

Trump’s newly enacted asylum policy means that migrants must now face those dangers for months while their cases are processed.

Traditionally, foreign visitors to the United States were able to apply for asylum at a port of entry, under what is known as “affirmative asylum.” They would then be allowed to stay in the United States while their case was adjudicated.

The Trump administration changed that in response to groups of asylum seekers from Central America who have arrived on the southern border over the past few years, including those in the high-profile “caravan” groups traveling together. The large number of pending cases in the asylum system last year lead to a lengthy backlog.

This week, a new policy was rolled out that requires asylum seekers to return to Mexico once they have applied. The asylum seekers would stay in Mexico but have multi-entry visas to attend court dates in the United States; the Department of Homeland Security has said that final decisions would be made within a year. As The Washington Post wrote Tuesday, the new policy is “one of the most dramatic changes to the American asylum system in decades.”

Even before the new asylum policy was implemented, some hopeful migrants were been murdered after being deported from the United States. The United States has also deported people back to some of the areas of Mexico worst hit by violent crime. That includes Reynosa, a border city in the northeast that has been called Mexico’s least secure city, and Tijuana, where last year’s migrant caravan ended — and where murders have exploded in recent years.

“The fact is, they’re deporting people to one of the most dangerous places on the border,” Ricardo Calderon, the top immigration official in the Mexican state of Tamaulipas, told The Post. “If people leave here to get something to eat, they’re going to be kidnapped.”

Eleanor Acer, the senior director for refugee protection at Human Rights First, said that Trump’s tweets Thursday showed how misguided this new policy has become.

“This tweet just confirms the absurdity of the Trump administration’s illegal policy of returning people seeking refugee protection to Mexico, a country that President Trump himself clearly understands is plagued by deadly dangers,” said Acer, who is in Tijuana monitoring the new policy. “Seeking asylum in the United States is legal; what the president is doing is not.”

Meanwhile, there are few signs that the violence in Mexican border areas is spilling over into the United States. In McAllen, the Texas city that lies just across the border crossing from Reynosa, there were no homicides in 2018, and crime is at its lowest rate in 34 years, according to the city government.

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