It was recently discovered that there could be a visa program that has made it easier for corporations in the California area to layoff their U.S. workers and hire immigrant workers at lower wages. This program became publicized when Southern California Edison Co. laid off a large portion of its labor force in exchange for inexpensive foreign labor. Senators are demanding a federal investigation into the issue.
See "Senators Seek Federal Investigation of Alleged H-1B Visa Abuse at Edison", Lisa Mascaro and Jim Puzzanghera, Los Angeles Times, April 9, 2015