All electoral systems have thresholds of representation: that is, the minimum level of support which a party needs to gain representation. Thresholds can be legally imposed (formal thresholds) or exist as a mathematical property of the electoral system (effective or natural thresholds).
Formal thresholds are written into the constitutional or legal provisions which define the PR system. In the mixed systems of Germany, New Zealand, and Russia, for example, there is a 5 per cent threshold in the PR section: parties which fail to secure 5 per cent of the vote nationwide are ineligible to be awarded seats from the PR lists. This concept had its origins in the desire to limit the election of extremist groups in Germany, and is designed to stop very small parties from gaining representation.
However, in both Germany and New Zealand there exist ‘back-door’ routes for a party to be entitled to seats from the lists; in the case of New Zealand, a party must win at least one constituency seat, and in the case of Germany three seats, to bypass the threshold requirements. In Russia in 1995, there were no back-door routes, and almost half of the party-list votes were wasted. Elsewhere, legal thresholds range from 0.67 per cent in the Netherlands to 10 per cent in Turkey. Parties which gain less than this percentage of the vote are excluded from the count. A striking example of this was the 2002 Turkish election, in which so many parties failed to clear the 10 per cent threshold that 46 per cent of all votes were wasted. In all these cases, the existence of a formal threshold tends to increase the overall level of disproportionality, because votes for those parties which would otherwise have gained representation are wasted. In Poland in 1993, even with a comparatively low threshold of 5 per cent for parties and 8 per cent for coalitions, over 34 per cent of the votes were cast for parties and coalitions which did not surmount it.
An effective, hidden, or natural threshold is created as a mathematical by-product of features of electoral systems, of which district magnitude is the most important. For example, in a district with four seats under a PR system, just as any candidate with more than 20 per cent of the vote will be elected, any candidate with less than about 10 per cent (the exact figure will vary depending on the configuration of parties, candidates, and votes) is unlikely to be elected.
