Act list MP John Bowscawen has been selected as his party’s candidate to contest the Mount Albert by-election.
I doubt that even he believes he could win but if he did then, as Kiwiblog explains, Hilary Calvert, number six on Act’s list would come in to parliament to replace him.
If National list MP Melissa Lee was selected as the candidate and won the next on her party’s list, Cam Calder, would enter parliament and if the Green candidate, list MP Russel Norman , won the seat then the Greens would get a 10th MP from the list.
With any of these scenarios the party which won the seat would also get an extra list MP and have a total of one more MP than they do now, as they would if a candidate who wasn’t already in parliament on the list won the seat.
If a Labour list MP stood and won then the next one on their list, Judith Tizard, would enter parliament but since no list MPs are standing if their candidate wins they keep the seat but wouldn’t get anyone else on the list and either way they finish with the same number of MPs as they have now.
However, if their candidate lost the seat Labour would not be entitled to another list MP so have one fewer MP than they do now.
The National-led government has a comfortable majority so that wouldn’t make any difference to the balance of power this time. But if the government and opposition numbers were very close a gain of an MP for one and a loss for the other, increasing the difference between them by two, could be significant.
I understand that once a list MP is in parliament s/he keeps her/his seat even if a by-election win gives her/his party one more MP than the list vote at the general election entitled them too.
I also understand why a list MP winning a seat his/her party held allows another list MP in because that retains proportionality.
But I don’t understand why a list MP winning a seat her/his party didn’t hold, which maintains proportionality, entitles the party to another list MP while a party which lost a seat isn’t entitled to another list MP in replacement when both scenarios upset proportionality.