legality." On illegal immigration Despite the passage of the act, the population of illegal immigrants rose from 5 million in 1986 to 11.1 million in 2013. In 1982, the Supreme Court forbade schools to deny services based on illegal immigration status in Plyler v. Doe. In 1986, Reagan signed the Emergency Medical Treatment and Active Labor Act (EMTALA), which forbade hospitals from denying emergency care services based on immigration status. Illegal immigration occurs when an individual enters the U.S. in any way without inspection from border personnel, or by overstaying a temporary visa. Researchers and immigration enforcement institutions use apprehensions data to estimate the number of undocumented immigrants present within the U.S. Customs and Border Protection (CBP) define apprehensions as, “the physical control or temporary detainment of a person who is not lawfully in the U.S. which may or may not result in an arrest”. In the years after IRCA (1986-1989), illegal immigration decreased slightly before returning to pre-IRCA levels. Multiple studies estimate the initial decrease as a result of legalization of previously undocumented immigrants who illegally crossed back-and-forth between the U.S. and Mexico continually (known as circular immigration) now being able to do so legally, subsequently avoiding apprehension. A long-term study published in 2011 analyzed border apprehensions from 1977 to 2000 and found that the decade after the IRCA amnesty program, apprehensions along the U.S.-Mexico border slightly decreased. Multiple studies also found that neither the amnesty provided under IRCA, nor the potential for a future amnesty program, encouraged illegal immigration in the long-term. While IRCA did not encourage illegal immigration, it failed to curb it. Some attribute this failure to a lack of focus on key determinants of immigration. A 2007 study in Hinckley Journal of Politics titled, The Ephemeral Immigration Reform and Control Act of 1986: Its Formation, Failure and Future Implications, defined these determinants as, “relative US wage levels, labor market flexibility, probability and cost of crossing the border, ability to find work, demographic changes, political turmoil, demand for labor in growing sectors, existing immigration networks and family relationships”. The same study highlighted the failed attempt of employer sanctions that established criminal and civil punishments on employers for knowingly hiring or continuing to employ undocumented immigrants. These sanctions resulted in little governmental oversight and enforcement, a lack of motivation and economic incentive on the part of employers to ensure all employees legal status prior to hiring (also