How Lobbying Affects Representation: Results for Majority-Elected Politicians

While most observers feel that interest groups influence parliamentary decisions, direct evidence on this topic is scarce. Matching parliamentary votes with referendum results helps to bridge this gap. Existing research for politicians of the Swiss Lower House of Parliament suggests that the number of sectional and cause interest groups affect the quality of political representation. We extend this analysis to majority-elected politicians of the Upper House and by more than 50 referendum decisions for the Lower House. Our results show that the pure number of sectional or cause groups does not affect defection of politicians from their constituents which suggests that the generalizability of the results may be limited