This post delves into wonkish matters arising from last week’s report by the Joint Standing Committee on Electoral Matters into last year’s federal election, and can thus be seen as a sequel to my earlier post on that subject. That post has a stimulating comments thread that I would like to see continue if anyone has anything to contribute specifically concerning the matters covered in this post. However, the comments thread below this post will serve as the usual open thread for general political discussion, it being past time for a new one.
On with the show. Among the more surprising recommendations of last week’s JSCEM report was the introduction of optional preferential voting. Whereas committee recommendations very often die on the vine, the chances of something becoming of this one shortened last week when both One Nation and the Centre Alliance indicated it would have their support, potentially giving it the numbers in the Senate over the opposition of Labor and the Greens. This prompted me to dig into data from last year’s state election in New South Wales, which offers the most proximate and generally useful pointer to how such a reform would play out at a federal election.
The New South Wales Electoral Commission is the only electoral authority that conducts full data entry of lower house ballot papers and publishes all the data, something the AEC only does for the Senate. The broader utility of this has been limited by the fact of New South Wales’ peculiarity of optional preferential voting, but as noted, there is a chance that may shortly change. I have aggregated this data to determine how each party and candidate’s preferences flowed between the Coalition and Labor, which no one else had done so far as I could see.
For those with a professional interest, this spreadsheet lays it all out seat by seat and party by party — for the lay person, the following table should suffice. It shows the aggregated statewide results from the state election, inclusive of the rate of exhaustion (i.e. voters who availed themselves of optional preferential’s opportunity to number neither Coalition nor Labor boxes), and the equivalent results from New South Wales from the federal election.
The reform’s attraction to the Coalition lies in the 40.0% exhaustion rate for the Greens vote, which split 82.2-17.8 in Labor’s favour federally. That alone would have sliced nearly 1% from Labor’s two-party preferred vote. However, the high exhaustion rate among all other minor parties, whose preferences in aggregate tend to favour the Coalition over Labor (think Hanson, Palmer and the religious parties) would have pared that back by around 0.3%. Such a change would probably have made a decisive difference in Macquarie (which Labor held by 0.2%) and Lilley (0.6%, and with an above-par Greens primary vote of 14.0%), and made life still more uncomfortable in Cowan (0.8%) and Eden-Monaro (0.8%, followed by 0.4% at the by-election).