Congressional Research Service, Jan. 13, 2016 - "Temporary visas for professional, managerial, and skilled foreign workers have become an important gateway for high-skilled immigration to the United States. Over the past two decades, the number of visas issued...
"Drawing on multiple data sources, the report suggests conclusions about the state of border security. Robust investments at the border were not associated with reduced illegal inflows during the 1980s and 1990s, but a range of evidence suggests a substantial...
"In 2009, the Department of Homeland Security (DHS) issued new guidance on immigration-related worksite enforcement. Under the guidelines, DHS “will use all available civil and administrative tools, including civil fines and debarment, to penalize and deter...
"[E]nhanced border enforcement may have contributed to a number of secondary costs and benefits. To the extent that border enforcement successfully deters illegal entries—an effect that is also difficult to measure since deterrence ultimately involves decisions...