State of the nation: trends in New Zealand voters’ polarisation from 2009–2018

ABSTRACT Voter polarisation, or the widening of differences between supporters of different political parties, is of growing concern in many nations. However, little is known about whether polarisation is on the rise in New Zealand. We address this lacuna by investigating temporal trends in voter polarisation in New Zealand (namely, those voting for the National party, Labour party, the Green party, and New Zealand First) from 2009–2018. Using a large national probability sample (the New Zealand Attitudes and Values Study; Ns = 2,820–39,287), we assessed polarisation across three domains: demographic characteristics, social and policy attitudes, and feelings towards each political party (affective polarisation). Evidence of polarisation was generally limited, with the most notable trends occurring in the public’s perceptions of societal fairness and attitudes towards inequality. These analyses provide insight into the magnitude and type of polarisation occurring across voters in a multi-party context.