You won't like the answer...
Mostly from self-identification, in surveys and polls.
The U.S. Census Bureau and Pew Research (a private center-left think tank) are the two “most respected” sources for estimates about illegal immigrants.
They also use statistics from the IRS, Labor Department, welfare agencies, law enforcement, etc. to refine their estimates.
So, the “official” number is 11-12 million illegals.
But, if someone else claims 20 million, it is basically impossible to prove who is right and who is wrong.
Thanks. That has been the answer I’ve found everywhere i look.
Everything is based on estimates - of course, what else could they use. I understand that.
259 million people in US in 1993.
326 million in 2017. (Clinton- 8yrs\Bush -8yrs\Obama -8yrs\Trump <1)
Estimated 4 million illegals in U.S. in 1993. 12 million in 2007.
The number almost tripled in 14 years and then stayed the same or less the next 10 years that included 8 years of Obama ?
I don’t buy it.