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.

在大多数民主国家，议会议员 (MPs) 是通过政党名单或地区选举产生的。我们使用德国选举制度中的不连续性来调查地区选举对国会议员是否符合党派路线的因果影响。地区选举不会因果地影响唱名投票行为，这可能是由于总体上高度遵守党派投票。分析每位议员的议会演讲，让我们能够克服议会投票方面的高党派纪律。使用文本分析和机器学习技术，我们创建了两种衡量议员演讲与党派路线的接近程度的方法。我们发现，在演讲方面，地区选举产生的议员与通过封闭党派名单选出的党内同僚并无不同。然而，