When institutions and issues change, voting changes

Voting behaviour is about how individuals cast ballots, but elections differ in the political issues that are at stake: control of government or making a decision about a major issue of policy. Electoral institutions also differ in how they translate votes into victory for one side or the other (Rose 1974: 9). The institutional differences between a referendum and a parliamentary election are categorical. In a referendum, an individual is asked to make a choice about an issue, and the outcome is a politically binding decision in favour of the policy that wins an absolute majority. By contrast, in a British parliamentary election, an individual votes for a party candidate; the outcome is then translated into MPs’ seats, and the outcome is that the party with the most seats gains control of government