How are employers going to know if a worker is legal or illegal?
On line database of SS numbers. Give employers 3 days to validate the work applicant's SS number. He can employ the fellow during the 3 days if he wants but if his SS number is phony he must be fired.
For businesses that don't want to go on line, they can validate over the phone with a private company which will contact the SS number database.
No jobs and 70% of illegal aliens will self deport.
Simple background check like they normally do with any other employee: photo ID (drivers license), birth certificate (which all natural U.S. citizens have) or naturalization papers / passport/visas/green-cards for legal immigrants.
It's a routine part of normal hiring practices.
Verify they have a legitimate Social Security number and other papers that match. When the guy the INS deported from your shop a week ago shows back up with a new name and new card --- it's a pretty good bet he's illegal --- but there's a machine shop in Michigan that did rehire someone like that ---- but they know --- most of their employees aren't speaking English at all --- that's another clue.
A profoundly relevant question. Federal, state and local PC laws actually actively prohibit making it possible. At the federal level, where does the buck stop?