OK, I knew that one of the anti-DACA talking points was BS: that unlawfully present people do not pay taxes.
They do using something called an Individual Tax Identification Number (ITIN). The ITIN is a tax
processing number issued by the Internal Revenue Service (IRS) to ensure
that people, including unauthorized immigrants, pay taxes even if
they do not have a Social Security number and regardless of their
immigration status.
The ITIN doesn't grant any sort of immigration status, but many immigrants have them.
The ITIN is a nine-digit number that always begins with the number 9 and
has a 7 or 8 in the fourth digit, for example 9XX-7X-XXXX. It seems to be it would be obvious if someone is trying to work without proper authorisation to the immigration authorities doing a record check.
A lot of countries levy a fine against people who are unlawfully present. Any funds paid should be considered a penalty for failing to properly comply with immigration status.
So long, and thanks for all the money.
See also:
The Facts About the Individual Tax Identification Number (ITIN)