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Most illegal immigration does not start off with a race across the border, but instead with government visas allowing foreigners to tour the United States or attend school, according to U.S. Rep. Rob Andrews.
Once those visas expire, the individuals go from being welcomed visitors to outlaws, vanishing into the population, the Democratic congressman said.
Andrews, who represents parts of southern New Jersey, made that point during an interview posted online on Sept. 12 with Townsquare Media New Jersey. Andrews is seeking re-election this November against Republican challenger Gregory Horton.
"The number-one source of undocumented people in this country is not people coming across the Mexican border," Andrews said. "It is people legally coming to the United States on a tourist visa or a student visa and then disappearing into the population and never being heard from again."
Pinning an exact number on a hidden population remains challenging, but most available estimates suggest Andrews is overstating how many illegal immigrants first arrived legally and stayed past the valid time limits.
That "overstay" population typically represents about one-third to roughly half of the country’s illegal immigrants. Therefore, about half to roughly two-thirds of illegal immigrants are generally those who entered the country illegally.
In fact, U.S. Homeland Security Secretary Janet Napolitano said in April that people overstaying their visas may account for fewer than 40 percent of illegal immigrants.
"That may be a high number, because what we have found is a lot of people who were marked as visa overstays had, in fact, left," according to a transcript of Napolitano’s remarks at a U.S. Senate Judiciary Committee hearing.
Defending Andrews’ statement, his chief of staff, Fran Tagmire, argued there are more visa overstayers than people who illegally crossed the Mexican border. But we told Tagmire that Andrews’ statement did not directly compare those two groups, but instead claimed overstayers are the "number-one source" of all illegal immigrants.
Now, let’s review the estimates we found.
A common measure for estimating the overstay population has been analyzing data from the immigration forms visa holders must file when they enter and leave the country.
Based on that methodology, in January 2003, the U.S. Immigration and Naturalization Service estimated that out of the 7 million illegal immigrants in January 2000, 33 percent were individuals who stayed after their temporary visas had expired.
In a May 2004 report, the U.S. General Accounting Office argued overstayers also include certain groups who had entered the country legally without visas and did not fill out those immigration forms.
Using three alternative data sources, the GAO report estimated the overstay population at 31 percent, 27 percent and 57 percent.
The most recent estimate we found was released in May 2006 by the Pew Hispanic Center.
The center estimated that out of between 11.5 million and 12 million illegal immigrants in 2006, "between 33% and 50% are visa overstayers." That estimate is based in part on the immigration form data used in the January 2003 analysis.
Still, data on overstayers has been considered unreliable, in part because of the incomplete collection of those immigration forms when foreign visitors leave the country.
The majority of illegal immigrants appears to be due to illegal border crossings, but it’s difficult to reach a precise number, said Edward Alden, an expert in immigration policy for the Council on Foreign Relations.
Our ruling
In an interview with Townsquare Media New Jersey, Andrews claimed the "number-one source" of illegal immigration "is people legally coming to the United States on a tourist visa or a student visa and then disappearing into the population and never being heard from again."
Data on the overstay population has been labeled unreliable, but most available estimates suggest such individuals are not the "number-one source." Those estimates indicate most illegal immigrants had entered the country illegally.
Most studies have said overstayers range from about one-third to roughly half of all illegal immigrants, and the U.S. Homeland Security Secretary said people overstaying their visas may account for fewer than 40 percent.
We rate the statement False.
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Townsquare Media, Interview with Congressman Rob Andrews, Sept. 12, 2012
PolitiFact Florida, Fla. Republican Rubio says close to half of illegal immigrants entered the U.S. legally, Jan. 18, 2010
PolitiFact, Democratic Rep. Gutierrez says 40 percent of illegal immigrants overstay visas, July 12, 2010
Pew Hispanic Center, Modes of Entry for the Unauthorized Migrant Population, May 22, 2006
U.S. General Accounting Office, Overstay Tracking: A Key Component of Homeland Security and a Layered Defense, May 2004
U.S. General Accounting Office, Overstay Enforcement: Additional Mechanisms for Collecting, Assessing, and Sharing Data Could Strengthen DHS’s Efforts but Would Have Costs, April 2011
U.S. Immigration and Naturalization Service, Estimates of the Unauthorized Immigrant Population Residing in the United States: 1990 to 2000, January 2003
U.S. Department of Homeland Security, Immigration Statistics, accessed Sept. 17, 2012
U.S. Department of Homeland Security, Illegal Alien Resident Population: Estimates of the Undocumented Immigrant Population Residing in the United States (October, 1996), updated December 2001
U.S. Department of Justice, Immigration and Naturalization Service Monitoring of Nonimmigrant Overstays, September 1997
U.S. Department of Justice, Follow-Up Report On INS Efforts To Improve The Control Of Nonimmigrant Overstays, April 2002
U.S. Department of Homeland Security, Estimates of the Unauthorized Immigrant Population Residing in the United States: January 2011, March 2012
Congressional Research Service, U.S. Immigration Policy on Temporary Admissions, Feb. 28, 2011
Congressional Research Service, Nonimmigrant Overstays: Brief Synthesis of the Issue, Jan. 15, 2010
Congressional Research Service, Mexican Migration to the United States: Policy and Trends, June 7, 2012
Migration Policy Institute, Testimony of Doris Meissner before the U.S. Senate Committee on Homeland Security and Governmental Affairs, March 30, 2011
Transcript of April 25, 2012 Senate Judiciary Committee hearing, accessed via Lexis-Nexis on Sept. 19, 2012
E-mail interview with Matthew Chandler, spokesman for the U.S. Department of Homeland Security, Sept. 18-19, 2012
E-mail interview with Doris Meissner and Michelle Mittelstadt, Migration Policy Institute, Sept. 19-20, 2012
Phone and e-mail interview with Edward Alden, a senior fellow with the Council on Foreign Relations, Sept. 19-21, 2012
E-mail interview with Fran Tagmire, chief of staff to Congressman Rob Andrews, Sept. 18-21, 2012
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