Being armed with a knife in a public place is illegal in most of Australia.
Ozpolitic denizen Valkie has publicly admitted to committing criminal acts.
https://www.lifehacker.com.au/2016/10/is-it-legal-to-carry-a-knife-in-public/ Quote:... In NSW, under the Summary of Offences Act 1988, Section 11C:
"A person must not, without reasonable excuse (proof of which lies on the person), have in his or her custody a knife in a public place or a school."
A 'knife' includes a knife blade, a razor blade and any other blade. The maximum penalty for this offence is 20 penalty units or two years in prison, or both. A "reasonable excuse" may be that you need the knife for work, for preparation of food in a public area, for recreational and entertainment purposes or for religious purposes. It is illegal to sell a knife to a person under the age of 16.
This law doesn't apply to knives that are considered prohibited weapons (for example, butterfly knives) which are illegal to own or carry at any point in time.
The same goes for Victoria, Queensland, Northern Territory and South Australia, which share the same restrictions on carrying knives. Tasmania changed its laws a few years ago to align with all the other states, except Western Australia, on this issue.
Western Australia have its own weapons laws, under Weapons Regulations 1999, which details different scenarios where carrying various controlled weapons in public would be acceptable. A knife is considered a controlled weapon.
So if you're carrying a knife with you for whatever reason, you better have a good excuse for it.