Legal Definitions - West Australian plan

The West Australian Plan is a type of voting system that falls under instant-runoff voting. Instant-runoff voting is a system of preferential voting that mimics a runoff election by using each voter's ranked preferences instead of a second round of voting. In the West Australian Plan, voters rank their preferred candidates, and the candidate with the least number of votes is eliminated. The votes for the eliminated candidate are then redistributed to the remaining candidates based on the voters' second choice. This process continues until one candidate has a majority of the votes.

Suppose there are three candidates running for mayor: Candidate A, Candidate B, and Candidate C. There are 100 voters, and they rank the candidates in the following order:

• 40 voters rank Candidate A as their first choice, Candidate B as their second choice, and Candidate C as their third choice.
• 35 voters rank Candidate B as their first choice, Candidate C as their second choice, and Candidate A as their third choice.
• 25 voters rank Candidate C as their first choice, Candidate A as their second choice, and Candidate B as their third choice.

In the first round of voting, Candidate C has the least number of votes (25), so they are eliminated. The votes for Candidate C are then redistributed to the remaining candidates based on the voters' second choice. Of the 25 voters who ranked Candidate C as their first choice, 15 ranked Candidate A as their second choice, and 10 ranked Candidate B as their second choice. After the redistribution of votes, Candidate A has 55 votes, and Candidate B has 45 votes. Since Candidate A has a majority of the votes, they are declared the winner.