Under MMP systems, the PR seats are awarded to compensate for any disproportionality produced by the district seat results. For example, if one party wins 10 per cent of the vote nationally but no district seats, then it will be awarded enough seats from the PR lists to bring its representation up to 10 per cent of the seats in the legislature. Voters may get two separate choices, as in Germany and New Zealand. Alternatively, voters may make only one choice, with the party totals being derived from the totals for the individual district candidates.
The proportion of seats allocated according to the two elements of the system vary from country to country. Lesotho’s post-conflict electoral system, adopted in 2002, contains 80 FPTP seats and 40 compensatory ones while Germany elects 299 candidates under each system.
Although MMP is designed to produce proportional results, it is possible that the disproportionality in the single-member district results is so great that the list seats cannot fully compensate for it. This is more likely when the PR electoral districts are defined not at national level but at regional or provincial level. A party can then win more plurality/majority seats in a region or province than its party vote in the region would entitle it to. To deal with this, proportionality can be closely approached if the size of the legislature is slightly increased: the extra seats are called overhang mandates or Überhangsmandaten. This has occurred in most elections in Germany and is also possible in New Zealand. In Lesotho, by contrast, the size of the legislature is fixed, and the results of the first MMP election in 2002 were not fully proportional.
