I have a suggestion...
If we didn't accept their "consular" cards as id they couldn't cash their checks, and couldn't be paid. Make positive id required for all money order purchases, we already have to show id to cash our checks.
Bansk and casinos are federally regulated, as are all the corner payday loan places.
The treasury currently accepts the id, but Homeland Security doesn't.
ID is gone, that means no money, no mortgage, no way to fly, that means they walk back home... (sorta poetic!)
They'll get paid in cash and then they won't even be paying taxes on it. Like a lot of them do now.