Mixed Member Proportional Systems

When Germany was reorganized in 1949, they developed the mixed-member proportional (MMP) system which tries to combines features of party list systems and the first-past-the-post system.

Half or more of the members of parliament are elected in single-member ridings like ours. The rest of the members are elected from party lists. Voters cast two votes, one to elect their local member and another to indicate the party they support. This gives voters the option of splitting their vote – i.e., casting a vote for their preferred party to form the government, but then also voting for a local candidate from a different party.

The party vote determines what portion of seats each party will have in parliament. If a party has not filled their fair share of seats through the riding elections, they receive additional at-large seats to be filled by some of their list candidates. This allows voters to still have an individual riding representative while correcting for the distorted results created by traditional first-past-the-post elections in ridings.

One leading example of how proportional representation would work at the federal level is the mixed member proportional model recommended by the Law Commission of Canada in 2004. Voters in each province elect the same number of MPs they will get anyway after the current census. You have two votes. You still elect locally two-thirds of the MPs. You also cast a regional vote by voting for the candidate or party you prefer. With your regional vote, you elect one-third of the MPs regionally so as to top-up the local results into close proportion to the popular support for each party. This is like the model used in Scotland and Wales, but with open lists, so no candidate is guaranteed a seat. It is called a regional-open-list Mixed Member model, or MMP for short. Other models could be chosen, and the design details of any model must be worked out by a citizen-based process.

In addition to Germany, these systems are now used in New Zealand, and in regional parliaments in Scotland and Wales. MMP was also proposed by the Ontario Citizens’ Assembly on Election Reform and by commissions in Quebec, New Brunswick and Prince Edward Island. MMP proposals were defeated in referendums in both PEI and Ontario.