They check for driver’s licenses - many,many illegal are driving without licenses.
Pomona is effectively East LA. I would guess atleast 50% of the people there are illegal or anchor babies.
It has a college and used to look like Mayberry until about 1975 when white flight struck California and everyone either moved to OC or out to Palm Springs.
You have foreign agitatiors as elected officials like Villaragosa and Newsom...they need to be voted out!