WEAPONS ACT 1999 - SECT 8
8 . Other articles carried or possessed as weapons
(1) Except as provided in subsections (3) and (5) and section 10, a person who carries or possesses an article, not being a firearm, a prohibited weapon or a controlled weapon, with the intention of using it, whether or not for defence —
(a) to injure or disable any person; or
(b) to cause any person to fear that someone will be injured or disabled by that use,
commits an offence.
Penalty: $4 000 or imprisonment for one year.
http://www.austlii.edu.au/au/legis/wa/cons...1999107/s8.html
http://www.austlii.edu.au/au/legis/wa/cons.../index.html#s16