City of Sydney Relationships Declaration
Other institutions such as the Registry of Births Deaths and Marriages no longer accepts an Australian Marriage Certificate as a form of ID – this creates an equal situation for both opposite sex and same sex couples as both are not allowed to present their relationship certificates as a form of ID.
Identity document
Not mandatory, but needed in almost all official documents, the CURP is the standardized version of an identity document. It actually could be a printed green wallet-sized card (without a photo) or simply an 18-character identification key printed on a birth or death certificate.