Published on the EPOP Blog on 4 May 2106

Voting Yes or No in a referendum is a substantially different choice. While Yes votes imply support for a change, No votes generally confirm the status quo. Such an imbalance is clear in the upcoming EU referendum in the UK. On the one hand, voters can choose to confirm Britain’s current status as a member of the European Union, while, on the other, they can opt for leaving the EU, with all the risks and uncertainties related to breaking an alliance that has lasted since the 1973. Considering these intrinsic differences between the two referendum options, how will the arguments from both sides of campaign influence the vote?

In my study “Voting under uncertainty: the effect of information in the Scottish independence referendum”, forthcoming in the Journal of Elections, Public Opinion and Parties, I explored this question in the context of the recent referendum campaign in Scotland. The study was conducted at BLUE Lab, University of Edinburgh, and involved a pool of around 180 participants that read a set of arguments in favour and against independence under different conditions. The reading material came only from publicly available sources and was presented in a completely ‘naked’ format – i.e. without mentioning any politicians, political parties or organizations of any kind.

The results show that information does influence voting decisions, but this effect crucially depends on two elements: the share of undecided voters, and the imbalance between a riskier Yes for a change and a safer No for the status quo. In the specific case of Scotland, the combination between a substantial level of indecision in the electorate and the uncertainties related to leaving the UK determined a one-sided persuasion effect of information, meaning that only the support for independence significantly increased after exposure to a mixed set of arguments. The support for independence raised especially among those who had ‘less to lose’ from a risky constitutional change in Scotland, because they did not expect any future improvement in their personal financial situation.

In light of the upcoming EU referendum, these findings suggest that providing voters with convincing arguments proves crucial especially for those who support a change of the status quo – in this case, the “Leave” campaign.