We hired a Canadian nurse who had a Pakistan ancestry. Turned out that she was in America with a green card, requested 0 income tax withheld. She had given us a fake address and was requesting all mail to go to a friends address which is different from where she lived. And she refused health insurance saying that if they had anything serious they would go home to Canada and take advantage of the free insurance there.
I flagged her to the IRS. And sooned fired her, because she was reporting a ton of overtime but didn't have the productivity to go with it. After I fired her, coworkers quoted her as saying "Everybody hates America".
If more people are as vigilant as you I feel optimistic about this war. Good going!
(She didn't file an anti-discrimination suit?)