What can I do if my employer forged legal documents for my employment?

I do not have the background to say whether you are under any legal obligation to report an employer's failure to collect a W-4 to the IRS or another body. Perhaps another attorney will comment. If not, I guess my question would be whether you should do anything. You have a job. Taxes were withheld. If too much was taken, you are entitled to a refund. If not enough was taken, you may have to pay some taxes. You can submit a new federal and state W-4 forms to make sure the correct amount is taken going forward. You may want to consider adjusting for the partial year. Unless there has been some enormous consequence, why cause a stir or create a rift? If it can be handled properly, perhaps you can point out your concerns so that this does not happen with other employees. The employer should regularly be collecting several documents, including the W-4s, a state New Hire Reporting form and the required INS documents to prove that a new hire is eligible to work in the U.S.