SAN DIEGO – President Donald Trump visited prototypes of his planned wall along the Mexican border and promised a huge payoff for U.S. taxpayers if Congress approves funding for construction. But he hasn't shown how.
Here's a look at some of his remarks Tuesday in San Diego and how they compare with the facts:
TRUMP: "It will save thousands and thousands of lives, save taxpayers hundreds of billions of dollars by reducing crime, drug flow, welfare fraud and burdens on schools and hospitals. The wall will save hundreds of billions of dollars — many, many times what it is going to cost."
TRUMP: "We have a lousy wall over here now but at least it stops 90, 95 percent. When we put up the real wall, we're going to stop 99 percent, maybe more than that."
THE FACTS: There are no measures of how well walls work.
Congress' main watchdog found that the government does not have a way to show how barriers prevent illegal crossings from Mexico. A Government Accountability Office report last year said U.S. Customs and Border Protection "cannot measure the contribution of fencing to border security operations along the southwest border because it has not developed metrics for this assessment."
That's after the government spent $2.3 billion from 2007 to 2015 to extend fences across 654 miles (1,052 kilometers) of border and more to repair them.
Without knowing how many crossers will be deterred by a wall, it is impossible to know how much money taxpayers will save in schools, hospital spending and other services.
Wall or no wall, the Border Patrol estimates that it stops 81 percent of illegal crossings by detaining people or getting them to turn around. A 2016 report prepared for the Department of Homeland Security by the Institute for Defense Analyses uses a different methodology and found that only 54 percent of people got caught.
TRUMP: "They re-established law and order in San Diego when they put up a wall."
FACTS: Construction of 14 miles (23 kilometers) of imposing border walls by the mid-2000s — along with more agents, technology and smaller barriers going back to the 1990s — brought a 95 percent decline in border arrests in the Border Patrol's San Diego sector from 1993 to 2017.
But the crackdown had serious consequences by pushing smugglers east to Arizona's remote mountains and deserts, where many immigrants die trying to cross.
The overall level of border arrests mostly stayed between 1 million and 1.5 million a year until the mid-2000s. Steady declines in recent years resulted in the lowest arrest tally last year since 1971.
TRUMP: "By the way, the state of California is begging us to build walls in certain areas. They don't tell you that, and we said no, we won't do it until we build the whole wall."
THE FACTS: Trump made a similar claim last month on Twitter but has yet to say who in California wants the wall. The state unsuccessfully sued to prevent construction of Trump's wall, claiming he was wrong to forgo environmental reviews.
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