The vote recommendations of a party that a voter opposes also influence their voting behavior in Swiss direct democratic votes. For example, a "Yes" vote recommendation from the Social Democrats leads people who see themselves as opponents of the Social Democrats to say "No" to this proposal. This response is true independent of the vote recommendations of other parties. Furthermore, the vote recommendations of the opposing party played a similar role to those of the party that one supports. "We were surprised that the effect of the opponents' party vote recommendations was so large," says Professor Strijbis.
The correlation between the vote recommendations of parties the voters oppose, and their vote choice was first demonstrated in a survey experiment on the "More Affordable Housing" bill on Feb. 9, 2020. In a representative survey, 2000 Swiss were randomly presented with the party vote recommendations of one of the major parties before being asked about their voting intention. Respondents were also asked whether they saw themselves more as opponents or supporters of the various parties. In particular, opponents of the Social Democrats and the Greens indicated that they would vote against the "More affordable housing" initiative when they were informed that those parties recommended voting “Yes” on the proposal.
Using existing survey data, the researchers then examined this correlation for all federal votes between 1981 and 2020. The responses of more than 90,000 survey participants were analyzed. According to Strijbis, the results from this analysis indicate that this is likely a general phenomenon and not specific to the vote on "More affordable housing."