NZ first changes candidate rules
New Zealand First leader Winston Peters (AAP)
NZ First has changed its rules to try to force its MPs to leave parliament if they resign or are expelled from the caucus.
The party's constitution now includes a clause requiring MPs to quit their seat in parliament within three days of resigning or being expelled from NZ First, or pay the party $300,000.
To enforce this, as a condition to being selected as a candidate, NZ First will require a document - intended to be a legally enforceable contract - to be signed.
The changes come after Brendan Horan was expelled from NZ First in 2012 following allegations he misappropriated money from his mother's bank account.
He refused to give up his seat and remains in parliament as an independent MP.
It's usually up to an MP to decide whether or not they stay in parliament if they resign or are expelled from caucus.
However, the Electoral Act outlines a number of circumstances in which an MP must lose their seat, such as if they are convicted of a crime punishable by two or more years in prison.