Final answer:
The Immigration Reform and Control Act (IRCA) requires employers to verify employees' employment eligibility and prohibits discrimination based on national origin or citizenship status.
Step-by-step explanation:
The statute that requires employers to verify the employment status of all employees, while not discriminating because of national origin or ethnic background, is the Immigration Reform and Control Act (IRCA). The IRCA was passed in 1986 and mandates that employers both ensure that their employees have the legal right to work in the United States by completing the I-9 form and avoid hiring undocumented immigrants. In addition to establishing employment eligibility verification processes, the IRCA prohibits employers from discriminating against individuals based on national origin or citizenship status, in compliance with federal law.