A proposal in Hong Kong would change the method of filling inter-election vacancies, reports David at Ahwa Talk. The electoral system for the Legislative Council is open-list PR, and currently by-elections are used to fill vacancies.
Most (all?) jurisdictions with OLPR systems simply take the next highest-ranking unelected candidate from the list of the departing member.
However, the Hong Kong proposal would take “The first candidate who has not yet been elected in the list with the largest number of remainder votes in the preceding general election.”
Average district magnitude is around five or six. David comments:
Maybe [proponents of this reform] assume that the individual candidate who captured that seat was a big reason for the party’s success… According to Carey and Shugart, low district magnitude in open list PR decreases the incentive for a candidate to cultivate a personal vote. In contrast, it is in high magnitude, open list PR where candidate preference matters more. This is because in a larger list, candidates have a stronger incentive to distinguish themselves from their fellow list members. Ultimately, we don’t really know why any individual is voting the way they are, but I think the Hong Kong government’s assumption requires more explanation.
I agree with David’s take on what the underlying assumption must be: that candidate reputation trumps party in Hong Kong. Indeed, the proposed method decreases the prominence of parties in that it departs from the normal working of OLPR by which is the list-PR component that first divides up the available seats, and only afterward that the “open” part comes into play in determining who gets those seats.
A potential benefit of the proposal, however, is that it should reduce the incentive of parties to rotate some of their legislators between elections. Doing so is common in OLPR systems–elsewhere (I do not know about Hong Kong)–and undermines the connection of elected legislators to the electorate. Under the Hong Kong proposal, a party would often forfeit the seat if it sought to swap out a member.
As for the Carey-Shugart (1995, Electoral Studies) we only claim that low-M OLPR places less premium on cultivating a personal reputation than does higher-M OLPR. The story is seen from the competing candidates’ point of view. From the voters’ point of view, however, smaller magnitudes and shorter lists undoubtedly increase the visibility of those who are elected, who win with greater shares of their party’s votes. I actually think this method for filling vacancies makes more sense for smaller district magnitudes than it would for larger. Whether it makes more sense than the usual party-centric way is an open question, and one that might not have a clear answer.