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Thursday, January 3, 2013

Unauthorized Aliens Residing in the United States: Estimates Since 1986



Ruth Ellen Wasem
Specialist in Immigration Policy

Estimates derived from the March Supplement of the U.S. Census Bureau’s Current Population Survey (CPS) indicate that the unauthorized resident alien population (commonly referred to as illegal aliens) rose from 3.2 million in 1986 to 12.4 million in 2007, before leveling off at 11.1 million in 2011. The estimated number of unauthorized aliens had dropped to 1.9 million in 1988 following passage of a 1986 law that legalized several million unauthorized aliens. Jeffrey Passel, a demographer with the Pew Hispanic Research Center, has been involved in making these estimations since he worked at the U.S. Bureau of the Census in the 1980s.

Similarly, the Department of Homeland Security’s Office of Immigration Statistics (OIS) reported an estimated 11.5 million unauthorized alien residents as of January 2011, up from 8.5 million in January 2000. The OIS estimated that the unauthorized resident alien population in the United States increased by 37% over the period 2000 to 2008, before leveling off since 2009. The OIS estimated that 6.8 million of the unauthorized alien residents in 2011 were from Mexico. About 33% of unauthorized residents in 2011 were estimated to have entered the United States since 2000, but the rate of illegal entry appears to be slowing. The OIS based its estimates on data from the U.S. Census Bureau’s American Community Survey.

Although increased border security, a record number of alien removals, and high unemployment, among other factors, have depressed the levels of illegal migration in recent years, the number of unauthorized aliens residing in the United States remains sizeable. Research suggests that various factors have contributed to the ebb and flow of unauthorized resident aliens, and that the increase is often attributed to the “push-pull” of prosperity-fueled job opportunities in the United States in contrast to limited job opportunities in the sending countries. Accordingly, the economic recession that began in December 2007 may have curbed the migration of unauthorized aliens, particularly because sectors that traditionally rely on unauthorized aliens, such as construction, services, and hospitality, have been especially hard hit.

Some researchers also suggest that the increased size of the unauthorized resident population during the late 1990s and early 2000s is an inadvertent consequence of border enforcement and immigration control policies. They posit that strengthened border security curbed the fluid movement of seasonal workers. This interpretation, generally referred to as a caging effect, argues that these policies raised the stakes in crossing the border illegally and created an incentive for those who succeed in entering the United States to stay. More recently, some maintain that strengthened border security measures, such as “enforcement with consequences,” coordinated efforts with Mexico to reduce illegal migrant recidivism, and increased border patrol agents, may be part of a constellation of factors holding down the flow.

The current system of legal immigration is cited as another factor contributing to unauthorized migration. The statutory ceilings that limit the type and number of immigrant visas issued each year create long waits for visas. According to this interpretation, many foreign nationals who have family in the United States resort to illegal avenues in frustration over the delays. Some researchers speculate that record number of alien removals (e.g., reaching almost 400,000 annually since FY2009) may cause a chilling effect on family members weighing unauthorized residence. Some observers point to more elusive factors when assessing the ebb and flow of unauthorized resident aliens—such as shifts in immigration enforcement priorities away from illegal entry to removing suspected terrorists and criminal aliens, or well-publicized discussions of possible “amnesty” legislation.



Date of Report: December 13, 2012
Number of Pages: 19
Order Number: RL33874
Price: $29.95

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