Choice and credible opposition are essential attributes of established representative democracies. There is academic debate on the extent to which the relationship between opposition and governing parties has become ‘blurred’ in policymaking and procedural running of parliament, but it is unclear how voters respond to it. In this paper, I study whether and how voters react to parliamentary distinctiveness (PD) of government and opposition parties.

I hypothesize that the relationship between the levels of government-opposition parliamentary distinctiveness and democratic legitimacy in general elections is curvilinear: moderate levels of distinctiveness are positively, but low and high levels are negatively related to the measures of democratic legitimacy. I also suggest that voters’ reaction to the lack of distinctiveness in the parliamentary arena is moderated by their group partisan identity – whether they supported the incumbent or the opposition at the previous elections.

I use multilevel analysis of survey data and legislative data spanning from the 1960s to 2010s from The Netherlands, United Kingdom, Canada, and Denmark, to study the effect of PD on individuals’ democratic satisfaction, trust in parliament, and electoral turnout. I operationalize government-opposition distinctiveness in behavioral terms as 1) a percentage of legislative votes in which parties voted similarly to the largest governing party; 2) a share of bills or proposals supported by the opposition or governing party. I compare the impact of PD on voters at the aggregate, group, and individual levels.