Additionally, a multi-party system provides voters with a choice of candidates, parties and policies to vote for. Historically, when a country only has one party, the result has been a dictatorship. In a democracy no one is above the law, not even a king or an elected President. This is called the rule of law. It means that everyone must obey the law and be held accountable if they violate it.
Democracy also insists that the law be equally, fairly and consistently enforced.