In New Zealand, waka-jumping is a colloquial term for when a member of Parliament (MP) switches political party between elections, taking their parliamentary seat with them and potentially upsetting electoral proportionality in the New Zealand Parliament. In 2001 legislation was enacted that required list MPs to leave Parliament if they waka-jumped; this law expired after the 2005 election. In 2018 a similar law was passed which requires a defecting MP to give up their seat on the request of their former party leader. Electorate MPs may re-contest their seat in a by-election, whereas list MPs are replaced by the next available person on the party list.