The government passed the Voluntary Assisted Dying Bill through the lower house of WA Parliament on Tuesday night.
The legislation was overwhelmingly supported with 45 votes in favour and 11 against, and was passed with no amendments.
Overall, the Legislative Assembly deliberated the bill for over 70 hours.
The legislation was introduced in August after two years of consultation and research in order to implement safe and compassionate voluntary assisted dying in WA.
Health Minister Roger Cook said they are committed to ensuring access to high-quality end-of-life care.
"We know voluntary assisted dying has widespread community support, it will provide Western Australians who are at the end of their life and experiencing intolerable suffering with an additional choice," Minister Cook said.
"Introducing this legislation is a complex and challenging task and I'd like to thank my colleagues in Parliament for their hard work and dedication in delivering the passage of this Bill through the lower house."
The next step is for the upper house to consider the legislation when it returns to parliament in mid-October.
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