Matching days on a passport and Arstotzkan ID card.
The date of birth (DOB) of an entrant is found on passports, identity cards, and grants of asylum. If an entrant provides two documents containing their date of birth, they must be verified for a possible discrepancy. If a discrepancy is found, the entrant cannot clear the dispcepancy and to avoid a citation inspector must either deny or detain the entrant.
They will only be incorrect either by only one digit or completely.