Electoral Systems, Party Systems, and Substantive Representation: An Analysis of Distortion in Western Democracies*

This paper examines the effects of party system features and election rules on substantive representation in parliamentary elections in Western democracies over a 50-year period. Substantive representation is conceived and measured as connections between the median voter and legislatures and governments. “Distortion ” is the short-term failure: distance between the median voter and the representative immediately after the election. Electoral choice and left-right positions of parties (from the manifesto data) are used to estimate median voter positions. The number of parties, party polarization, and the election rules all independently affect distances between voters and their legislative representatives after an election (“distortion.”) But party system polarization seems to be the predominate factor shaping distortion of governments’ relationship with the median voter. Examining the party system effects under different election rules helps clarify the causal connections between legislative and government levels