Illinois Sen. Dick Durbin claimed Wednesday that 40 percent of illegal immigrants in the U.S. overstayed legal visas.

Verdict: True

Estimates indicate that the proportion of illegal immigrants who overstayed visas has hovered around 40 percent for decades.

Fact Check:

As Congress debates a legislative solution for the Deferred Action for Childhood Arrivals (DACA) program, the White House has proposed a pathway to citizenship for 1.8 million “Dreamers,” along with stricter immigration enforcement, cuts to family-based migration and $25 billion in border wall funding. Democrats like Durbin have expressed skepticism about the proposal and the utility of a border wall.

“Forty percent of all those who are in this country undocumented came here by visa overstays,” Durbin claimed on the Senate floor. “So if your true goal is the reduction of the undocumented in America and trying to make sure there is legal status for as many as possible and you are looking at the incremental growth each year, you wouldn’t look to the border first. You would look to the visa overstays first. Those are the ones who are slipping through the system, who should be policed and monitored with new technology.”

The Department of Homeland Security (DHS) defines a visa overstay as a “nonimmigrant who was lawfully admitted to the United States for an authorized period” — such as for business, study or pleasure — “but stayed in the United States beyond his or her lawful admission period.” Border crossers, on the other hand, never obtained legal authorization to enter the country.

Although the DHS collects comprehensive data of foreign arrivals by air and sea, precise data on the overstay population is not available because U.S. ports of entry historically lacked the infrastructure to collect departures data. (Technology initiatives and legislation have improved data collection at air and seaports, but the DHS still faces obstacles collecting data on departures via land routes.)

With the use of DHS and other demographic data, Robert Warren and Donald Kerwin of the pro-migrant Center for Migration (CMS) estimate that around 4.5 million – or 42 percent – of the roughly 11 million illegal immigrants in the U.S.  in 2014 were overstays.

Warren estimates that the overstay population has been in the ballpark of Durbin’s 40-percent-figure since the 1980s. “The percentage has been at that level for about 40 years,” he told The Daily Caller News Foundation. “Anyone who says it’s between 40 and 45 percent has been correct for about 40 years.”

The overstay population has remained relatively stable in part because a significant number of overstays attain legal status or return home.

“We’ve found that people who come in as overstays often leave the population,” Warren explained. “As in, they go back home or adjust their status to legal residence … But, for whatever reason, they are more likely to leave the illegal population than border crossers.”

Some older estimates have ranged between about 30 and 60 percent. But many previous estimates also stemmed from methodology devised by Warren, who was previously a demographer for Immigration and Naturalization Services (INS).

Warren expressed confidence in his most recent calculations. “We have better numbers now,” he told TheDCNF. “Not only better numbers for the current period, but for previous years.”

The overstay population could, however, proportionally start to increase as two-thirds of new illegal immigrants in 2014 were overstays, more than double its 1995 share. Annual flows of border crossers – most of whom are from just five Central American countries and Mexico – have sharply declined beginning in 2000, while visa overstays from other parts of the world remained relatively stagnant.

DHS data indicate that citizens of less developed countries tend to have higher visa overstay rates. The agency estimates, for instance, that almost 25 percent of Djiboutians and 20 percent of Eritreans who entered the U.S. by air or sea on temporary business or pleasure visas who were supposed to depart in fiscal year 2016 overstayed their visa – compared to nearly zero percent of Norwegians and Singaporeans.

The Trump administration has taken steps to apply more rigorous scrutiny to new applications for temporary visas and crack down on nations whose citizens demonstrate high rates of overstay. But some proponents of lower immigration are hopeful that further reforms, along with prominent proposals like a border wall, are in the works.

“If the wall doesn’t go beyond being a symbol, and it just becomes an excuse to avoid doing those other things—like stopping overstays—than we have a problem,”Mark Krikorian, director of the Center for Immigration Studies, told The Daily Signal in March. “I don’t get that sense from this administration.”

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