Possessing any object specifically for the purpose of self-defence, lethal or non-lethal, is a criminal offence in Australia. There are many women, raped and/or murdered, who would have been liable to prosecution had they been carrying anything that might have saved them.

https://www.dailytelegraph.com.au/news/opinion/an-assault-on-our-right-to-selfprotection/news-story/f743f8b76f21a586a6efb2396c9b2f8d

List of assaults, rapes, killings & home invasions for 2018