Employment Law Questions? Ask an Employment Lawyer.
If the worker has no employment authorization, then she is working unlawfully, and your employment of her is a criminal violation of federal law. Naturally, it's pretty common for people to employ undocumented aliens as domestic workers -- and the federal government (at least as long as President Obama remains in office) is not going door to door looking for illegal workers.
There's no trick to you continuing to pay her. But, if you get caught, the fines can be stiff. The biggest risk is that the worker is injured at your home, and then sues you for negligence/premises liability, because you do not have workers compensation insurance coverage. If you want to avoid this risk, then talk to your homeowners insurance agent and see if you're covered. Otherwise, the risk could be a lot bigger than anything that the government may impose.
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