About 4 years ago the government tried to prosecute an employer for having illegal immigrants using that basic logic. The employer said he suspected that about

About 4 years ago the government tried to prosecute an employer for having illegal immigrants using that basic logic. The employer said he suspected that about half his employees had forged documents, but he obviously didn't know of any specific case. (The Feds trapped him by telling him they were doing a murder investigation and asking him for information about his employees. Don't talk to cops.) IIRC the prosecution failed, although they did put the guy through the wringer in the meantime.