It's been said that Winston Peters is NZ's great political survivor. He's also been the beneficiary of a fair bit of legal luck along the way.
Let's assume, purely for the sake of argument, that it turns out Mike Sabin actually didn't need to resign from Parliament. Which means that there didn't need to be a by-election in Northland back in 2015. Which in turn means that Winston Peters shouldn't really be the electorate MP for Northland.