Elections lie at the very heart of modern democracy. They are typically the occasions when citizens become most directly engaged in the political process; they determine the identity of those who will govern, often for four or five years; and they significantly influence how that governing power can be exercised.

The rules that govern elections therefore matter too, for they can have a major impact upon outcomes. Had different electoral rules been in place, George W. Bush might not have been elected to the American presidency in 2000 and Tony Blair might never have secured a majority of the seats in the British House of Commons. Had less proportional rules been used, Italy might not have been quite so plagued by ‘revolving door’ governments for the last sixty years. Conversely, had proportional representation not been chosen as part of the interim constitution of 1993, South Africa might not have achieved such remarkable democratic stability after its hard-fought transition from white-only rule.

Given the importance of electoral rules, it matters that we understand where those rules come from. Three questions in particular demand our attention. First, who has the power to choose the electoral system? To what extent do politicians control the decision process? To what extent are they constrained or can they be entirely displaced by others, including citizens, judges, and foreign powers? Second, what interests or values do these choices serve?