What is a referendum, and how is it different from a vote in parliament?

A referendum is a vote in which the people themselves, not their elected representatives, decide a particular proposal, law or political issue. A vote in parliament is the opposite arrangement: citizens choose representatives at an election, and those representatives then vote on each law for them. In a referendum the voters skip the middle step and answer the question directly.

The word shows the idea. It comes from Latin and literally means "to carry back": a proposal that must be carried back to the people. Imagine a messenger who is not allowed to settle the matter and has to return home to ask. That is why referendums are usually reserved for big questions, such as changing a constitution or a voting system, where elected officials may not have the legitimacy, or the wish, to decide alone.

Not every referendum has the same force. A referendum may be binding, so that the result becomes policy, or advisory, working like a very large opinion poll that leaders may or may not follow. Some are mandatory, because a rule says a vote must be held, for example for constitutional changes in Australia, Ireland, Switzerland and Denmark. Others are optional, held because the government, the legislature or enough citizens with signatures demand one.

Most countries that use referendums are also representative democracies, so the two tools sit side by side: parliament does the everyday lawmaking, and the voters are called in for the occasional big decision.