The proposal is set for a vote requiring 2/3 of the 70 local legislators to support it for passage. While the 27 members who are overtly pro-democracy could veto the bill, such a move amounts to a game of chicken, as they might not be able to subsequently negotiate anything better.
As a co-founder of The Center for Election Science, I've spent nearly a decade studying electoral system design with a focus on game theory. I believe there's a simple way to mitigate the divisiveness of this proposal. We have to convert from an inflexible all-or-nothing approach to a "tunable" compromise-friendly approach. Here's how.
Consider that what's really at issue is not whether Beijing has influence on the process, but how much influence. Virtually everyone accepts the reality, however painful, that Beijing will have some influence. The current proposal allows the 1200-member nominating committee to select 2-3 nominees via Approval Voting, with those candidates then being elected by a popular vote using Plurality Voting, aka First-past-the-post.
The catch is, all nominees must be approved by at least half of the committee. But that 50% threshold is tunable. Imagine it was instead set to something like 25%, for example. And imagine there was no limit on the number of nominees. This would still give Beijing a great deal of influence, but would offer Hongkongers a significant amount of real choice.
The problem is, Plurality Voting is not well-suited for elections with more than two candidates. The vote splitting (or "spoiler") effect means that an unpopular candidate may win simply because the majority who opposes him is split between two or more rivals. We saw this in the US state of Maine in 2014, when they reelected an unpopular Republican governor merely because his Democratic rival was challenged by a strong left-leaning independent. This predictably led to calls for independents to betray their conscience and vote Democrat.
But this is easily fixed if we extend the use of Approval Voting to the general election. As Hong Kong legislator Regina Ip Lau Suk-yee said herself:
"approval voting" has the advantage of fostering the selection of a consensus candidate, a person who attracts the least objection and is most capable of accommodating diverse interests and factions.My advice to pro-democracy activists might be to suggest Approval Voting in the general election, combined with a the removal of the 2-3 candidate limit. In other words, let all candidates who clear the 50% threshold run in the general election with Approval Voting. Then leave that 50% threshold on the negotiating block for a future time. In this way, both sides can negotiate something that is flexible rather than playing a rigid game of chicken.