• Keith Locke is a former Green MP.
The bill before Parliament to stop party-hopping has been misnamed. The Electoral (Integrity) Amendment Bill should be called the Party Conformity Bill because it threatens MPs with ejection from Parliament if they don't conform to party dictates.
Personal political integrity will be constrained, except on a few selected "conscience" issues, like the assisted dying legislation, where MPs are free to vote as they want.
The bill contravenes the New Zealand Bill of Rights Act provisions guaranteeing freedom of speech. The idea that individual MPs should be legally restrained in what they say is abhorrent in a parliamentary democracy.
It also runs counter to the spirit of parliamentary privilege, which gives MPs more freedom than the rest of us to say what they want, without the danger of libel suits, when speaking in the chamber.
No other Western democracy has laws to stop party-hopping. In fact West Germany has a constitutional provision that once elected MPs are "representatives of the whole people, not bound by orders and instructions, and subject only to their conscience".
It is common in the British Parliament to see MPs "crossing the floor" and it can serve a useful function. Recently several Conservative MPs crossed the floor to provide a majority for a Labour Party amendment requiring that the final Brexit deal be brought back to Parliament for a vote.
Under our proportional system parties rise and fall, often helped by rebels from other parties. In fact, each of the smaller parties which have won seats in our MMP Parliaments have initially been led by rebel MPs from existing parliamentary parties.
Former Labour MP Richard Prebble was not an MP when he became Act leader but the other rebel MPs setting up new parties were all sitting in Parliament at the time.
Jim Anderton left Labour mid-term to set up NewLabour (which later merged into the Alliance). Peter Dunne split from Labour to form Future NZ (which later became United) and Tariana Turia went from Labour to the Maori Party. Winston Peters went from National to found NZ First. Rod Donald and Jeanette Fitzsimons left the Alliance for the Greens and Hone Harawira exited the Maori Party for Mana.
Rather than distorting the proportionality of Parliament, new parties set up by the rebels have provided the electorate with more political choice.
Sometimes a rebel MP claimed, with some justification, that he or she was protecting a choice that had previously been available. Anderton, for example, said NewLabour was heir to a Labour tradition which had been betrayed by Labour turning to Rogernomics.
In 1999, speaking against an earlier party-hopping bill, Green co-leader Rod Donald reminded the House that "had this bill existed prior to the last  election, we [Donald and Fitzsimons] would have been removed from this House and denied our opportunity to stay here for the full parliamentary term".
Fitzsimons and Donald had been elected as Alliance list MPs in 1996 but left the Alliance Party in 1997 along with the rest of the Green Party. If these two MPs had been excluded from Parliament in 1997 it is unlikely the Greens would have reached the 5 per cent threshold for parliamentary representation in the 1999 election, or that Fitzsimons would have won the Coromandel seat.
This is something for the current Green caucus to ponder before continuing to support the current party hopping legislation.
Previously, the Green Party and its co-leaders have been strongly opposed, in principle, to party-hopping legislation. As Donald said in the 1999 speech to Parliament, MPs are not "party robots", "MPs must retain the right to be answerable to their own consciences, and political parties must not be allowed to take away from voters the power to unelect Members of Parliament." As a Green MP at the time I made similar points in the debate on that bill.
The provision in the current legislation that two-thirds of a party's caucus must approve ejection of a member from Parliament does not provide much protection for dissidents.
Take the recent example of Green MPs Kennedy Graham and David Clendon publicly calling for the resignation of co-leader Metiria Turia. They were then excluded from the Green caucus and could have then been ejected from Parliament, after various bureaucratic processes had been gone through, if the current party-hopping legislation had been operational.
Graham and Clendon's public criticism angered many party members, but others said it highlighted a party issue that needed urgent attention. The matter was resolved by the two MPs agreeing to withdraw from the party list for the election, which was surely better than invoking a law.
Resorting to legislation to get rid of an MP potentially involves the courts, which are not equipped to handle political or process disputes within parliamentary caucuses. It is safer, and more democratic, to leave decisions on the makeup of Parliament to the voters.