The Pew Research Center's unauthorized alien population estimate for 2012 was 11.2 million, which included some 8.1 million unauthorized workers in the U.S. civilian workforce. The department maintains data on several measures that can be used to examine the performance of its worksite enforcement program. Enforcement activity by the Department of Labor (DOL) is also relevant to a discussion of federal efforts to address unauthorized employment. DOL, which is responsible for enforcing minimum wage, overtime pay, and related requirements, focuses a significant percentage of its enforcement resources on low-wage industries that employ large numbers of immigrant—and presumably large numbers of unauthorized—workers. More specifically, the INA Section 274A provisions, sometimes referred to as employer sanctions, make it unlawful for an employer to knowingly hire, recruit or refer for a fee, or continue to employ an alien who is not authorized to be so employed. Enforcement of the prohibitions on unauthorized employment in INA Section 274A—or worksite enforcement—has been the job of DHS's U.S. Immigration and Customs Enforcement (ICE) since 2003. Under the worksite enforcement guidance issued in 2009, homeland security remains a primary concern of ICE's worksite enforcement program. Penalties

As discussed above, employers who violate INA prohibitions on the unlawful employment of aliens may be subject to civil and/or criminal penalties. Criminal investigations may result in employers and other individuals being charged with crimes other than unlawful employment, such as document fraud or harboring unauthorized aliens, and being subject to the relevant penalties for those violations. With respect to criminal arrests, the potential population of employers and workers committing worksite-related criminal violations is not known. More generally, the values of the various measures for the years shown seem quite small relative to the estimated size of the unauthorized workforce. Conclusion

The data provided here on Final Orders, administrative fines, administrative and criminal arrests, criminal indictments and prosecutions, and criminal fines offer a way to assess DHS's worksite enforcement strategy over the years and in its current form.
Under current Department of Homeland Security (DHS) guidance on immigration-related worksite enforcement, the agency uses available civil and administrative tools, including civil fines and debarment, to penalize and prevent unlawful employment. According to 2012 estimates, there are some 8.1 million unauthorized workers in the U.S. civilian labor force.
DHS's U.S. Immigration and Customs Enforcement (ICE) is responsible for immigration-related worksite enforcement, or enforcement of the prohibitions on unauthorized employment in Section 274A of the Immigration and Nationality Act (INA). The INA Section 274A provisions, sometimes referred to as employer sanctions, make it unlawful for an employer to knowingly hire, recruit or refer for a fee, or continue to employ an alien who is not authorized to be so employed. Today, ICE's worksite enforcement program is focused primarily on cases that involve critical infrastructure facilities and cases involving employers who commit "egregious" violations of criminal statutes and engage in worker exploitation.
Employers who violate INA prohibitions on the unlawful employment of aliens may be subject to civil monetary penalties and/or criminal penalties. Criminal investigations may result in defendants being charged with crimes beyond unlawful employment and being subject to the relevant penalties for those violations.
Various measures are available to examine the performance of ICE's worksite enforcement program. They include Final Orders for civil monetary penalties, administrative fines, administrative arrests, criminal arrests, criminal indictments, criminal convictions, and criminal fines and forfeitures. In addition to examining annual changes and trends in the various performance measure data, these data can be considered in relation to the estimated size of the unauthorized workforce or the potential number of employers employing these workers. When considered in this context, ICE's worksite enforcement program can seem quite limited.
Enforcement activity by the Department of Labor (DOL) is also relevant to a discussion of federal efforts to curtail unauthorized employment. DOL, which is responsible for enforcing minimum wage, overtime pay, and related requirements, focuses a significant percentage of its enforcement resources on low-wage industries that employ large numbers of immigrant—and presumably large numbers of unauthorized—workers.