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The dubious statistic getting the DHS secretary in trouble with President Trump

Department of Homeland Security Secretary Kirstjen Nielsen and President Trump have had a contentious relationship as illegal border crossings increase. (Video: Patrick Martin/The Washington Post)

“The Border Patrol’s May arrest numbers are due to be released early next month, and immigration hawks, including the president, now treat them as a kind of barometer for [Homeland Security Secretary Kirstjen] Nielsen’s performance.”
— Reporting by The Washington Post, based on interviews with Trump administration officials, May 24, 2018

The president is unhappy with Nielsen and judges her by the number of people caught trying to cross the U.S.-Mexico border, The Post reported.

President Trump feuds with members of his Cabinet all the time. What’s curious here is that he seems to have chosen a dubious performance metric for the homeland security secretary. Basically, he’s saying Nielsen is bad at her job because U.S. officials are catching more undocumented immigrants at the border this year than in 2017. Let that sink in for a minute. Trump apparently wants border agents to be catching fewer people instead.

What we have here is a Catch-22, brought on by the president’s iffy use of data.

U.S. Customs and Border Protection reports monthly on the number of people who were apprehended trying to cross the southern border. If this number rises, what does it mean?

Is it an indicator that more undocumented immigrants are getting through the border? That seems to be Trump’s view. But it could also mean illegal immigration is declining, because border-crossers are being caught in greater numbers. Looked at another way, if the number of apprehensions went down, would that reflect fewer attempts to cross the border or U.S. officials failing to catch as many people as before?

Because of these reasons, tracking the number of apprehensions is a flawed way to measure the effectiveness of border agents. Since these Trump comments come from anonymous administration officials, though, we will withhold Pinocchios. Let’s take a look.

The Facts

Southwest border apprehensions peaked most recently at 1.6 million in 2000 and have been in decline for the better part of the following two decades, partly because of technology upgrades, tougher penalties post-9/11, a decline in migration rates from Mexico and a sharp rise in the number of Border Patrol officers.

For fiscal 2017, Customs and Border Protection reported 303,916 apprehensions at the U.S.-Mexico border, the lowest in more than 45 years. Fiscal 2017 covered the period from October 2016 through September 2017, or the tail end of President Barack Obama’s term and most of Trump’s first year.

“The number of apprehensions reported by the DHS is very small — the lowest number of since 1971 — and in that year there were only 1,500 Border Patrol officers, whereas today there are 19,000 officers,” Douglas S. Massey of Princeton University, the co-director of the Mexican Migration Project, previously told The Fact Checker. “The number of apprehensions per officer are at their lowest point since 1942.”

Trump is proud of his 2017 record. “We’re doing a lot of work on security, generally speaking, security and border — border security. The border’s down over 40 percent,” he said on May 24 in a Fox News interview, using outdated figures for border apprehensions.

In recent months, apprehensions have been spiking. Year over year, they were down 17 percent for January — then they jumped 42 percent for February, 206 percent for March and 244 percent for April, when 38,234 people were apprehended at the border. So 2018 is not looking good for the record books.

“For decades, the U.S. Border Patrol has used apprehensions of unauthorized immigrants as its primary proxy indicator of total illegal inflows,” according to a report by the Department of Homeland Security’s Office of Immigration Statistics issued in September 2017.

The department defines “illegal inflows” as the people who make it into the United States. DHS estimates this figure, using “the odds of successful entry multiplied by apprehensions” as its formula, according to the Center for Immigration Studies. From 2000 to 2016, annual apprehensions declined from 1.6 million to 408,870, a 75 percent drop. According to the DHS report, that would suggest a corresponding drop in illegal inflows “somewhat greater than 75 percent,” assuming that border agents improved their apprehension rate from 2000 to 2016, as other data suggest.

But some experts say apprehensions are not a solid indicator of how many people make it into the United States. For one thing, this figure doesn’t account for people who overstay their visas. In fiscal 2016, U.S. officials reported 408,870 southwest border apprehensions and 544,676 visa overstays. For another, it’s difficult to draw good inferences on the number of people who make it through based on the number who get caught.

“While DHS employs a number of concrete metrics to track border security operations, it is difficult to precisely quantify illegal flows because illegal border crossers actively seek to evade detection, and some flows are undetected,” said the DHS report, which was issued partly in response to a Trump executive order on immigration. “As a result, any effort to quantify illegal flows or calculate an overall enforcement success rate must rely on one or more estimation techniques. Measurement is also difficult because of the diversity and complexity of the enforcement mission along the United States’ 2,000-mile land border with Mexico.”

No matter. The president appears to be focused on border apprehensions, and he’s blaming Nielsen for the recent spike instead of economic factors and long-term trends that are also in play. The Post’s Josh Dawsey and Nick Miroff reported:

At one point, Trump noted the border numbers were lower under [chief of staff and former Homeland Security Secretary John] Kelly and wondered aloud why Nielsen could not perform as well, according to these officials, who spoke on the condition of anonymity to describe the private meeting.
As illegal crossings are once more on the rise and Trump hears a cascade of criticism from conservative allies, Nielsen finds herself on the receiving end of the president’s visceral anger about immigration, seeing the issue as the reason he won in 2016 and a key to his politicking ahead of the midterm elections.

Along with the number of apprehensions, CBP reports the number of “inadmissibles” encountered by border agents. Adding this number to the monthly total, however, gives a muddled picture.

Unlike the people who are apprehended, “inadmissibles” are not taken into custody. They’re not necessarily trying to cross illegally, and they’re usually turned back without a fuss. CBP describes them as those “who are seeking lawful admission into the United States but are determined to be inadmissible, individuals presenting themselves to seek humanitarian protection under our laws, and individuals who withdraw an application for admission and return to their countries of origin within a short timeframe.”

In any case, the same 2018 trend applies for both apprehensions and for the combined monthly total of apprehensions and inadmissibles, according to CBP data. Both have been shooting upward in recent months.

But studies indicate that none of these numbers — apprehensions, inadmissibles or the sum of both — is a reliable measure of how effective the United States is at preventing illegal immigration on the border. Trends over many years are significant. Year-to-year and month-to-month movements, not as much.

2011 study by the Rand Corp., commissioned by the Department of Homeland Security, explores this paradox. A lower number of apprehensions could mean border-crossers are staying away for fear of being caught, but it could also mean authorities are catching fewer and, therefore, that more are settling in the United States. The inverse of this is that “increases in border control effectiveness could well increase the number of apprehensions, without such increases signaling greater flow of illegal crossers,” according to the Rand study, which recommended other ways to measure border agents’ performance.

Customs and Border Protection sometimes tries to have it both ways, the study noted.

“Interestingly, U.S. Customs and Border Protection has reported annual decreases in apprehensions as evidence of effectiveness, presumably on the theory that decreases reflect fewer crossing attempts, rather than diminished apprehension success rates. Indeed, the U.S. Government Accountability Office reports that CBP explained increases in apprehensions made at checkpoints in some border sectors to improved CBP operations and decreases in apprehensions in other sectors to the deterrent effects of improved CBP technologies and increased staffing. Clearly, a measure that reflects successful performance whether it rises or falls has limited value as a management tool.”

According to the GAO, U.S. border officials said “apprehensions increased” at an Arizona checkpoint “because the sector maintained nearly full-time operations at all sector checkpoints during fiscal year 2008” and because “the Border Patrol increased the number of operational checkpoints in the sector from 10 in fiscal year 2007 to 13 in fiscal year 2008.”

The GAO report, from 2009, said, “Border Patrol officials said that apprehensions decreased in other sectors in part due to the deterrent effect of increased Border Patrol presence and infrastructure, and initiatives to criminally prosecute illegal aliens.”

So apprehensions rose in one sector because a beefed-up law enforcement presence led to more captures, and they fell in other sectors because a beefed-up law enforcement presence scared people away. Either way, the Border Patrol had a banner year!

Doris Meissner, who was commissioner of the former U.S. Immigration and Naturalization Service from 1993 to 2000 and is now director of the Migration Policy Institute’s U.S. immigration policy program, testified in Congress about the problems with using the apprehensions statistic.

“Apprehensions are insufficient as sole measures of effectiveness because they count activity or workload, not persons,” Meissner testified in 2013. “In the past, the Border Patrol has cited both surges and reductions of apprehensions as evidence of deterrence. Apprehensions are a valid proxy for reduced flows and deterrence, particularly when they demonstrate a trend, as has occurred with the steep apprehension declines in recent years. However, they do not provide an estimate of the total size of the illegal flow. More sophisticated, valid measures for estimating actual flows across the border are long overdue.”

A Migration Policy Institute spokeswoman, Michelle Mittelstadt, added that CBP collects other data that would give a fuller picture.

“The number of border apprehensions is the best publicly available measure of the federal government’s effectiveness in preventing unauthorized crossings, but it is only a partial snapshot of what CBP uses internally to measure its effectiveness and direct its enforcement strategies,” Mittelstadt said. For example, she said, the agency also collects data on “ ‘turnbacks’ (people deterred from illicit entry because of the presence of the Border Patrol or other deterrence) and ‘gotaways’ (those who are counted making their way into the U.S.).”

The 2017 DHS report talks about the need for better estimates of “illegal inflows.” Neither the White House nor a spokesman for Nielsen would respond to our questions.

The Bottom Line

This fracas reminds us of “Alice in Wonderland,” and specifically the part where the queen’s gardeners are painting white roses red.

“Why the fact is, you see, Miss, this here ought to have been a RED rose-tree, and we put a white one in by mistake; and if the Queen was to find it out, we should all have our heads cut off, you know. So you see, Miss, we’re doing our best, afore she comes, to–”

The point is that this number doesn’t say much about illegal immigration on a month-to-month or year-to-year basis, as Trump seems to think. Instead, the apprehension total is a fuzzy and limited snapshot that can be spun in many different ways.

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Not the whole story
“We’re doing a lot of work on security, generally speaking, security and border — border security. The border’s down over 40 percent."
in a Fox News interview
Thursday, May 24, 2018