Drivers in Colorado can now opt out of choosing a gender on their driver's license, while Tasmania looks to be the first state to drop gender from birth certificates altogether. Is it time for New Zealand to follow?

In New Zealand, citizens have the freedom to change their gender identity on citizenship records. Kiwis can choose to have passports marked with male, female or X, without the need to amend the details on birth certificates or citizenship records.

To change the gender identity on a New Zealand driver's licenses, you need only apply to the NZ Transport Agency or change it when it's time to replace your licence. It's more freedom than many countries provide, but some think it's time to scrap gender on forms of identity altogether.

Tasmania is considering the move. Transgender rights organisation Transforming Tasmania wants to see the change which has been supported by the Greens, local newspaper the Advocate reports, but the Government said it wants further consultation on the matter.

Transgender activist Lexie Matheson supports the idea for New Zealand, telling TVNZ the country should follow in Tasmania's footsteps, adding that she disagrees gender is defined by a person's anatomy at birth.

The idea has faced backlash in Tasmania, however, where the Labor party said it would not support the Greens' amendment, which would prevent the registrar of births, deaths and marriages from including a child's sex on birth certificates.

The proposed legislation came as a surprise to many, as Tasmania has some of the most discriminatory laws in Australia for transgender, gender diverse and intersex people, LGBTI advocate Rodney Croome told theGuardian. After all, until 2000, it was illegal to cross-dress in the state.

Tasmanian law currently requires that a person undergo sexual reassignment surgery before they can register their change of sex with the registrar of births, deaths and marriages.