AILSA CHANG, HOST:
Well, as Congress has worked toward a deal to keep the government open, President Trump has continued to make the hard sell for his border wall. He tweeted just last night that it will be beautiful and that it will save the country billions of dollars per month once it's completed. That is on top of data he presented during the explosive meeting he had with Nancy Pelosi and Chuck Schumer last week.
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PRESIDENT DONALD TRUMP: San Diego - illegal traffic dropped 92 percent once the wall was up. El Paso - illegal traffic dropped 72 percent, then ultimately 95 percent, once the wall was up. In Tucson, Ariz., illegal traffic dropped 92 percent.
CHANG: The Democratic leaders contested those numbers on the spot. And afterwards, Pelosi had this to say.
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NANCY PELOSI: I didn't want to, in front of those people, say, you don't know what you're talking about.
CHANG: Well, we have brought in an expert to help fact-check the president's claims. Doris Meissner is a senior fellow with the Migration Policy Institute. She was also commissioner of the U.S. Immigration and Naturalization Service during the Clinton administration. Welcome.
DORIS MEISSNER: Thank you. Glad to be with you.
CHANG: So what do you make of the president's numbers that you just heard?
MEISSNER: Well, he's using very high numbers. But it's also the case that as border enforcement has increased and as investments have been made, the numbers in those locations certainly went down. But they went down, and the apprehensions went down, because of a broad combination of enforcement measures that were put in place over time.
The important thing about fencing and barriers is that fencing and barriers are the single most expensive investment in that menu of things, and so it needs to be used sparingly, and it needs to be used in combination with people and all of the other technologies.
CHANG: When you were heading INS, you oversaw the installation of border fencing, as expensive as it was. What convinced you that that would be a good use of resources? Let's talk about the merits of more fencing.
MEISSNER: Yes. The merits are strong, and the merits have proven to be valid. Where fencing is important is where there are heavily populated areas on both sides of the border that basically touch each other. People go back-and-forth regularly for economic reasons - shopping and so forth - but also to go to school, also to work.
However, that makes the border porous. And so what you want to do with fencing is have fencing exist in a way that channels the movement across the border through legal ports of entry and then redirects the crossings that would be unauthorized crossings to the outskirts, where enforcement personnel have the upper hand because they can see what's happening and they can then stop crossings that are not authorized.
CHANG: So you have mentioned that building more fencing - building more walls, if you will - would be expensive. The president, on the other hand, is saying that it would bring cost-savings - billions of dollars a month. What do you think? I mean, have parts of the wall that already exist now proven to be cost-saving despite the initial high cost of building that fencing?
MEISSNER: I'm not sure that I would say cost-saving. I think that it's been shown and that we know that fencing is a good investment where it makes sense to use it. But it's also true that fencing requires a lot of maintenance. The maintenance for fencing is an expensive, ongoing carrying cost.
And across the board, fencing plan for the southwest border is overkill. It's not needed. Much of the border is very remote, very rural. You can deal with those parts of the border with aircraft, with sensors, with lighting, with tracking measures of one sort or another in a much more cost-effective way.
CHANG: You think those measures would give more bang for the buck than more fencing.
MEISSNER: That's exactly what I think, yes.
CHANG: Doris Meissner is director of the U.S. Immigration Policy Program at the Migration Policy Institute. Thank you very much.
MEISSNER: Thank you.
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