So long, and thanks for all the money.

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)