Such data tells only part of the story, says the former director of the U.S. Immigration and Naturalization Service, the country's immigration enforcement agency before the creation of the current office, Immigration and Customs Enforcement. But, she added, it does indicate that security at the Texas-Mexico border has improved since the last time the issue was fiercely debated in Washington.
Last week, a bipartisan group of U.S. senators and President Obama pitched their ideas for comprehensive immigration reform to the public, and both proposals included border security as a major piece. Also last week, fiscal year 2012 statistics released by U.S. Customs and Border Protection indicated that agents in Texas apprehended more people attempting to enter the country illegally, 172,335, well ahead of any other state that borders Mexico. In Arizona, 124,631 people were apprehended. California and New Mexico's figures are 54,246 and 5,661, respectively.
Doris Meissner, the former commissioner of the U.S. INS and a senior fellow at the Migration Policy Institute, said that as those figures are dissected, it should remain clear that arguments about border security cannot rely solely on whether apprehension figures are high or low.
"Apprehensions is an important indicator, it is an insufficient indicator and it's an indicator than can legitimately be interpreted either way," she said. "First of all we always have to remember that apprehensions represent an enforcement action, not a person. And so with apprehensions for the whole [southern] border the apprehensions were 365,000 enforcement actions."
Meissner said that according to methodology used by the Congressional Research Service, the data probably represented about 269,000 people being apprehended.
A January 2012 study by Marc Rosenblum, an immigration policy specialist for the Congressional Research Service, supports Meissner's stance. It found three specific shortcomings with apprehension data.
One example, which directly supports Meissner's argument, is that the data counts events and not people.
"Thus, an unauthorized migrant who is caught trying to enter the country three times in one year counts as three apprehensions in the data set," Rosenblum writes. "To the extent that apprehensions are interpreted as a direct indicator of illegal migration, the data therefore may overestimate the actual number of people trying to cross the border."
He also cited as potentially problematic the exclusion of three different groups: unauthorized immigrants who cross the border successfully (including those who enter without inspection, use fraudulent documents or overstay their visas); certain unauthorized immigrants who fail to cross the border (those who are denied entry at a port or are apprehended by local, state or other federal law enforcement officials, and those who die attempting to cross); and "would-be" unauthorized immigrants who are persuaded from trying to cross the border by factors like "remote deterrence," when they are dissuaded in their communities.
The last shortcoming the CRS study cites is that apprehension data doesn't take into account how many illegal border crossings are largely influenced by "push-and-pull" factors, including economic trends and demographic shifts.
Despite the shortcomings with apprehension data, Meissner said that the efforts to secure the border shouldn't be discounted within the debate on immigration reform.
According to CBP headquarters, the agency has more than doubled the number of U.S. Border Patrol agents since 2004 to more than 21,300.
That statistic, along with apprehension data, should be considered as factors that reflect positive trends, Meissner said.
"Certainly some people are going to use the same tired language that we've heard for 10 years, that we can't do anything until the border is secure," she said. "But for anybody that wants to listen, for anybody that wants to look at the case at this point, the border is an entirely different place than it was 10 years ago. You have a dramatic reduction in apprehensions in the last 10 years. Just in the last five or six years it's fallen another 50 percent, so it's a very different picture where unauthorized crossing is concerned."
Federal lawmakers have received the message, Meissner said. She cites U.S. Sen. John McCain, R-Ariz., as an example of how attitudes are shifting. McCain is a part of the "Gang of 8" that unveiled its plans for reform last week.
"When he was running for re-election [in 2010] and certainly when he was running for president, he became very, very harsh in his assessment of insufficiencies of border enforcement," she said. "And now when you see what he did a week ago, at the Gang of 8 press conference he is saying very clearly, 'Border security has improved. It's improved to the point where it's not where I'd like to see it be. But it's sufficiently improved that we need to be talking about broader changes.'"
Despite the progress, she said, there is still a chance for border security debates to derail immigration reform negotiations. During a hearing this week before the U.S. House Judiciary Committee, some members indicated they were open to breaking up a larger reform plan into different components, The New York Times reported. Meissner said that although that may address some of the issues, like the DREAM Act or a temporary guest-worker program, it would still leave many issues unresolved, like addressing the estimated 11 million people in the country illegally and preventing a future influx of unauthorized immigrants.
"What it does is cherry-pick politically -- it takes the measures that have real support and pulls them off from the harder measures, gets them passed, allows the Congress to say, 'Okay, check the box,'" she said. "Then the things that are really hard don't have a broad base of political support and those don't get done and as a country we still have too many unaddressed issues."
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