1. Employers are responsible for verifying the employment eligibility of new hires by completing Form I-9 within 3 days of hire and retaining records for 3 years. They may face criminal or civil penalties for knowingly hiring or continuing to employ unauthorized workers. 2. Employees have anti-discrimination protections based on national origin or citizenship for employers with 4 or more employees. Exceptions exist for citizenship discrimination against lawful permanent residents, refugees, and asylees under certain conditions. 3. The government enforces employment eligibility and anti-discrimination laws through penalties for violations including fines, cease and desist orders, and jail time for patterns of violations.