Strategic Abstention in Parliamentary Voting

Observing legislators’ voting behavior plays a crucial role in the parliamentary process, both in terms of representation and in terms of accountability. When a MP votes either for or against a proposal, and so for or against his party’s policy line, this action can be observed by both voters and party leaders, who can react accordingly. However, a third voting option exists: Abstaining. While party voting unity, as measured by the Rice Index, often reaches near-perfect levels in parliamentary regimes, this presumes that abstention is random. However, abstaining is an attractive option for a MP who does not wish to vote against either his party line, his own ideology, or his voters’ interests. By analysing the recorded votes in a legislature where all votes are recorded, and noted as ‘aye’, ‘nay’, ‘abstain’ or ‘not present’, this paper explores how MPs consciously avoid publicly taking a stance in order to maximize their utility vis-à-vis their party, voters and ideology. The dataset used contains the complete voting records of the Swedish Riksdag, where all final votes are recorded, over a 17-year period, covering nearly 4 million individual voting decisions made by 942 MPs. It combines these with a series of unique surveys of Swedish MPs, with response rates of over 90%, covering five parliamentary terms. Due to the high and consistent response rate, there are no concerns about selection bias in terms of survey respondents. The effect of electoral incentives on MPs is further analysed by exploiting the change of the electoral system from a closed-list to a semi-open list in 1997. By using the individual vote totals of MPs as a measure of their independence from their party, it is possible to assess the effect of both constituency pressures and MPs’ desires for a personal vote on their subsequent floor behaviour.