Roll-Call Votes in the German Bundestag: A New Dataset, 1949-2013

This letter introduces a comprehensive data collection on roll-call votes (RCVs) in the German Bundestag between 1949 and 2013. RCVs are one of the most important data sources on parliamentary behavior. Beyond producing legislative output, RCVs put the positions of Members of Parliament (MPs) and party groups on the public record, serve party leaders as an instrument with which to monitor backbench behavior, and enable opposition parties to obstruct parliamentary business (Saalfeld 1995a). RCVs from various parliaments have been used to investigate, among others, party competition and legislative coalition formation, the strategic behavior of individual MPs and legislative parties, party unity and intraparty politics, and MP responsiveness to voters and other outside interests (for example, Carey 2007; Carrubba, Gabel and Hug 2008; Eggers and Spirling 2016; Hix 2004; Hix and Noury 2016; Poole and Rosenthal 1997). Empirical research can rely on comprehensive longitudinal roll-call data for a number of countries, most notably the US Congress (for example, Lewis et al. 2017; Poole and Rosenthal 1997),1 the European Parliament (Hix, Noury and Roland 2005), and the British House of Commons (for example, Eggers and Spirling 2016; Norton 1975); on some cross-country comparative datasets for shorter periods of time (Carey 2007; Coman 2015; Hix and Noury 2016; Sieberer 2006); and on numerous contemporary and historical single-country datasets.2 For the German Bundestag, RCV data has thus far only been available for limited periods of time (Ohmura 2014b; Saalfeld 1995b; Sieberer 2010; Stratmann 2006). At the same time, the Bundestag is an attractive parliament to study. It is one of the most powerful legislatures in a parliamentary democracy (Sieberer 2011); its internal organization is rather elaborate (Saalfeld 2000); and its mixed electoral system offers attractive opportunities to analyze one of the most fundamental aspects of legislative behavior: the effect of electoral rules on legislative voting (for example, Manow 2015; Sieberer 2010; Sieberer 2015). The datasets described here contain information on individual voting behavior and a wide array of variables that characterize the MPs and RCVs they voted on. The data are freely available to the academic community at Harvard Dataverse.3 In this letter, we describe the structure of the datasets, present descriptive information on key variables and discuss potential research questions to be addressed with the data.