You approve or deny depending on matching data. Early on, if data doesn't match, they just go. Later on, there is stricter procedure. They might turn up missing documentation if you question them instead of straight denying them. As the game goes on, there can be more discrepancies with their documents, and you have to be keen on all of them. It's fun in a challenging way. You look over a paper, let them in, get in trouble. "What? Damn it, the one time I didn't check gender." xD