Originally Posted by
ESpen36
So the government would not care if you left by air, then returned by land or sea without a passport scan, and then tried to board another international flight to leave again? Or would the system be flagged because there was no record of you returning before departing again? (assuming a US Citizen/LPR)
I've left on military aircraft, and private and biz aircraft and via land and sea borders without giving any info to the CBP and no passport info has been given on manifests (yes now GA aircraft must get "permission" but that is another story).
I've used one way tickets, official passports and tourist passports and dual citizen passports to travel and it is not all linked or tracked. Yes there are systems in place where countries share certain passport information, but that does not normally constiture any exit swipes (for the few places that actually swipe). Also, the US is not good at tracking exit controls via air (especially with airline reporting systems varying amongst carriers), and does not via land in most cases.
Even passport stamps are not a good indication for reasons too many to note here.