| Especially since the government gets from all non-immigrants: - Common carrier arrival manifests. - Visa stamp process arrival record and I-94 issuance. [4] - US-VISIT biometrics collection on arrival. [2] - Form I-9 when starting a new job. [3] - Form AR-11 every time they move. [1] - Common carrier departure manifests. - Tax returns. As far as I can tell the only people who "sneak out" do so by crossing the border into Canada and the US should have access to that data from Canadian authorities after the fact also. [1] https://www.uscis.gov/ar-11 [2] https://www.dhs.gov/xlibrary/assets/usvisit/usvisit_edu_trav... [3] https://www.uscis.gov/i-9 [4] https://i94.cbp.dhs.gov/I94/ |