David McGee, a former Clerk of the House, has written the definitive book on parliamentary rules and practice in New Zealand. Yesterday in this paper he made an appeal for new rules to keep MPs in their seats for a full term.
Early resignations have become so common since the adoption of MMP, he feared that "increasingly, membership of Parliament is seen as being at the convenience of each member, perhaps more accurately the member's party, rather than as an obligation undertaken when elected".
This attitude seems rife among list members, who can be readily replaced by their party without a byelection. But electorate MPs have also resigned in greater number since 1996, some taking advantage of the rule that no byelection need be held if a general election is less than six months away.
McGee suggests these trends should be discouraged by requiring electorate members to post a bond they would forfeit if they did not complete the term, and setting a rule that a list member could not be replaced, which would reduce the party's votes in Parliament.
The rule for list members would probably work, the House is normally finely balanced and no party wants to relinquish a vote. A bond might be less effective. MPs determined to leave would probably bear the cost. But first the question needs to be asked, do early departures really matter?
McGee suggests they do for two reasons, one of principle the other practical. "Members in the final year of a Parliament," he wrote, "can and should be expected to contribute to its work for a full term." That implies a three-year legislative programme may be marginally harmed by changes of personnel.
More important may be the principle at stake. Candidates for Parliament offer the public their service for three years. It is an important understanding on both sides, a candidate would fiercely deny any suggestion before the ballot that he or she might not intend to serve a full term.
It was that solemn undertaking that John Key could not give at this year's election that has caused him to relinquish the role of Prime Minister. But in doing so he said he would leave Parliament before completing this term, taking advantage of the sixth month rule once the election date is set.
Labour electorate MPs Phil Goff and David Shearer have already left this Parliament when it suited them, as has National's Tim Groser and Greens Russel Norman and Kevin Hague. McGee says, "Membership of Parliament ought not to be a mere convenience for political parties, not should it be a status that can be discarded lightly."
But nor should it be a prison. If an MP has lost interest for any reason - perhaps their career is going no further or they have found Parliament too frustrating - it is surely better for the country that they give their seat to someone else rather than serve out their time, especially if the cost of a byelection can be avoided.
If the status of Parliament is suffering as McGee fears, there is no evidence of it. This year, as always, many will be fighting to get in.