Undocumented immigrants can get an ITIN, and many do use them to pay taxes. The IRS really doesn't care where you got your money from, so long as they get their cut.
Where undocumented immigrants won't be able to file their taxes is if they used a counterfeit SSN to be employed, but even in those cases they pay anyways through standard withholding. Most Americans don't know you can adjust withholding, nevermind undocumented immigrants.
Where undocumented immigrants won't be able to file their taxes is if they used a counterfeit SSN to be employed, but even in those cases they pay anyways through standard withholding. Most Americans don't know you can adjust withholding, nevermind undocumented immigrants.