Does a District Mandate Matter for the Behavior of Politicians? An Analysis of Roll-Call Votes and Parliamentary Speeches

In most democracies, members of parliament (MPs) are elected either through a party list or by a district. We use a discontinuity in the German electoral system to investigate the causal effect of a district election on an MP’s conformity with the party line. A district election does not affect roll-call voting behavior causally, possibly due to overall high adherence to party-line voting. Analyzing the parliamentary speeches of each MP allows us to overcome the high party-line discipline with regard to parliamentary voting. Using textual analysis and machine learning techniques, we create two measures of closeness of an MP’s speeches to the party line. We find that district-elected members of parliament do not differ, in terms of speeches, from those of their party peers who have been elected through closed party lists. However, both speeches and voting correlate with district characteristics, suggesting that district elections allow districts to select more similar candidates rather than changing MPs’ behavior.