You do not normally have to answer police questions after you are arrested by police officers in New South Wales, except for providing information about your identity.
In fact, you should never participate in a police interview until and unless you have first sought the advice of a lawyer.
However, there are situations where the law does require you to answer questions, including where you are suspected of certain terrorism-related offences.
There are also disclosure requirements in certain pieces of legislation, including the Road Transport Act, National Parks and Wildlife Act, Meat Industry Act and Local Council Act.
Authorities must advise you of these obligations and formally warn you that not answering required questions may amount to an offence.
If you are unsure of these requirements, always ask to contact a lawyer.