Claim: When visa holders exit the United States and enter Mexico, "if they leave through a land port of entry we literally have no clue if they are still here or have returned to their country of origin."
Fact-check: Fact-checking O'Rourke's claim about border land departures
Verdict: mostly-true
Organisation: PolitiFact
Author: Miriam Valverde
Date published: 2019-02-15T00:00:00