MMP overhang: How co-ordinated voting can weaken proportionality

Analysis byReynold MacphersonRotorua Daily Post·11 Nov, 2026 03:00 PM4 mins to readUnder MMP, the party vote largely determines how many seats each qualifying party receives, writes Reynold Macpherson. Photo / NZME New Zealanders should be able to expect that a political party’s share of parliamentary seats will broadly reflect its share of the party vote.That is the central promise of mixed-member proportional representation, or MMP.When the rules allow co-ordinated voting tactics to weaken that relationship, criticism is justified. However,