Electoral law, electoral behaviour and electoral outcomes : Australia and New Zealand compared

Australia has compulsory voting, and New Zealand voluntary voting. Australia has preferential and New Zealand simple plurality voting. Australia has an elected upper house and New Zealand a unicameral parliament. What effect do these differences in electoral law have on electoral behavior and electoral outcomes in the two countries? Aggregate data (from 1960 to 1984) and survey data (from around the end of the 1970s) are used to investigate this question. In terms of influencing electoral behavior, it appears that these factors produce no more than marginal variations. However the comparison of preferential and simple plurality voting does suggest that these alternative procedures have the potential to generate different electoral outcomes. Overall, though, it seems that historical, cultural and political factors which steer Australia and New Zealand towards similarity predominate over features of the electoral systems which might otherwise tend to give rise to differences between the two countries. (Internat. Polit. Science Assoc.)