Unauthorized immigration has become a prominent topic in the 2016 election. In recent debates, town halls, and television ads, heated rhetoric has often won out over the facts. In this post, I present evidence on undocumented immigration and immigration enforcement in order to ground the debate in fact and debunk several prominent myths.

1. Most US immigrants are not here illegally. There are currently 41.3 million foreign-born individuals living in the United States, and less than one-third of those (an estimated 11.3 million) are unauthorized. Furthermore, many unauthorized immigrants do not arrive by crossing the US-Mexico border; instead, as many as 45 percent overstay visas they obtained legally for tourism, education, or temporary work.
    
2. Most evidence shows that undocumented immigrants are not stealing jobs from or lowering the wages of American workers.

• Research evidence suggests that overall, US-born and immigrant workers complement each other, rather than compete in the labor market. Scholars have found scant evidence of immigrants harming the employment opportunities of low-skilled US workers. There is some evidence that immigrants do displace small shares of low-skilled and/or African American native workers, though these impacts could be mitigated by native workers moving to other labor markets or receiving better job opportunities when immigrants fill the lowest-level positions. For some workers, efforts to provide education and training could help support this labor mobility.
• Urban Institute researchers argue that immigrant and native workers compete for different jobs, even in the low-wage sector. Furthermore, the US Chamber of Commerce has stated that removing the eight million undocumented workers would not lead to eight million job openings for unemployed Americans, as these two groups often have different, complementary skills and the removal of these immigrants would also remove “entrepreneurs, consumers, and taxpayers.”
• While some scholars have shown that undocumented immigration lowers the wages of a small subset of low-skilled US workers, most evidence shows that there is no effect or only weak negative effects of immigration on most native workers’ wages, with some researchers even showing positive wage effects.

3. Crime has not increased as a result of increased immigration. Over the same period that unauthorized immigration was increasing, violent and property crime both fell dramatically. There is little data on crime among undocumented immigrants specifically, but among immigrants overall, incarceration rates are lower for foreign-born men than they are for the native-born population. While the number of foreign-born individuals in federal prisons increased from 2005 to 2010, the proportion of the total federal prison population that is foreign-born has remained relatively constant since 2001.
    
4. Undocumented immigrants pay taxes and Social Security. Undocumented immigrants contribute an estimated $11.6 billion in taxes to federal, state, and local governments. They pay sales taxes and property taxes, even when renting. Furthermore, at least 50 percent of undocumented immigrants file and pay income taxes every year.
    
5. Deporting all 11 million undocumented immigrants is infeasible. A recent report finds that mass deportation would likely cost between $400 and $600 billion dollars over a 20-year period. In order to accomplish this in the next two years, as some candidates have promised, the United States government would have to add thousands of federal immigration officers, hundreds of thousands of beds in detention centers, hundreds of immigration courts, and thousands of immigration lawyers. Additionally, this deportation policy is estimated to shrink the labor force by 10 million workers and reduce real GDP by $1 trillion.
    
6. Building a wall on the border will not necessarily halt the influx of undocumented workers. Several candidates have stressed the need for a physical wall on the US-Mexico border to stop undocumented immigration. Previous efforts to cover the entire length of the border have failed because of fiscal and environmental challenges. To build a wall across the entire southern border of the United States, roughly 2,000 miles, would be extremely expensive. Some have even argued that heightened border enforcement decreases the fluid and circular nature of migration and actually discourages immigrants from leaving the United States once they arrive. Additionally, a border wall would not stop immigrants who overstay legally obtained visas and become undocumented.
    
7. President Obama’s executive orders do not legalize undocumented immigrants. President Obama established the Deferred Action for Childhood Arrivals (DACA) in June 2012. DACA provides temporary relief from deportation and work authorization for young people who meet certain eligibility criteria, including continuous US presence since June 2012. DACA gives undocumented immigrants a temporary, revocable status that must be renewed every two years at the discretion of the Department of Homeland Security. The program does not provide a path toward a legal immigration status or citizenship. The president also announced some expansions to DACA in late 2015, which are currently being considered by the Supreme Court. Additionally, in November 2014, President Obama established the Deferred Action for Parents of Americans and Lawful Permanent Residents, which would provide undocumented immigrants who pass security and criminal background checks, who have been present in the United States since January 2010, and who have children that are US citizens or lawful permanent residents with a three-year work permit and deferred action. This program is also currently before the Supreme Court.