Christopher Luxon Promises MMP Referendum If Re-Elected, Winston Peters Calls It A 'Power Grab'Jo Moir Political editorWinston Peters has labelled the prime minister's call for a referendum on the MMP voting system "inexplicable" and a "power grab". Luxon told Newstalk ZB on Thursday morning a referendum on MMP is "something we should consider" and he wants to see it happen next year. Labour's leader Chris Hipkins said a referendum was not necessary, because the 2011 referendum on the matter showed people clearly favoured MMP. Luxon told Newstalk ZB "rightly or wrongly New Zealanders have chose when they've been given the opportunity the MMP system". He said New Zealanders "need to understand it's not first-past-the-post in an MMP system - that is unrealistic".