The MMP system preferred by the majority of PR supporters in the 2018 referendum had a threshold of 5% for voters for a party to elect top-up MLAs. So I’ll start with the three parties which got more than that threshold.
The NDP got 49.4% of the three-party vote, almost enough for a majority, but my projection shows them with 43 of the 87 seats, one short of a majority. However, NDP voters would have been better represented in the Interior and North.
Note: this is only a simulation
In any election, as Prof. Dennis Pilon says: "Now keep in mind that, when you change the voting system, you also change the incentives that affect the kinds of decisions that voters might make. For instance, we know that, when every vote counts, voters won't have to worry about splitting the vote, or casting a strategic vote. Thus, we should expect that support for different parties might change."
Better regional representation
In the 14 seats of the Interior (including Kamloops—Thompson but not Cariboo), NDP voters would have elected six MLAs rather than four. That might have included Sadie Hunter from Kamloops and Aaron Sumexheltza from Fraser—Nicola (the Lower Nicola Indian Band), or maybe Toni Boot from Penticton or Nicole Cherlet from Revelstoke. The winners would be the regional NDP candidates who got the most votes (other than those who had won local seats), so my examples are those who had gotten the highest percent of the vote.
The Interior would have elected eight local MPs from larger ridings, and six regional MLAs for top-up seats: six Liberals, six New Democrats, and two Greens. Green voters might have elected Nicole Charlwood from Nelson and Amanda Poon from Kelowna, or Andrew Duncan from Rossland or Dan Hines from Kamloops. I have used the “largest remainder” calculation, which Germany used until recently, because it is the simplest and most transparent. If Party A gets 6.4 seats and Party B gets 5.6 seats, who gets the 12th seat? Party B.
In the ten Northern seats NDP voters would have elected four MLAs, not just two. That might have included Nicole Halbauer from Terrace and Kitsumkalum First Nation (Skeena) and Scott Elliott from Quesnel (Cariboo North), or Anne Marie Sam from Nechako Lakes and Nak’azdli Band, or Joan Atkinson, Mayor of Mackenzie District (Prince George—Mackenzie). Green voters would have elected someone like MacKenzie Kerr from Prince George. The North would still have ten MLAs (six local, four regional MLAs for top-up seats).
Liberal voters would have elected 31 MLAs, only 3 more than the 2020 result, but they would have elected 17 MLAs from the Lower Mainland instead of only 10, and they would have elected 3 MLAs from Vancouver Island instead of none at all.
Green voters would have elected 13 MLAs. Three from the 16 ridings of Vancouver-North Shore, such as Jeremy Valeriote from Whistler, Bridget Burns from East Vancouver, and Kelly Tatham from Vancouver-Mount Pleasant, or Kim Darwin from Sechelt, or Ian Goldman from Vancouver-Fairview. One from Burnaby-Tri-Cities-Maple Ridge such as Cyrus Sy from New Westminster. One from Surrey-Delta-Richmond like Peter van der Velden from Delta or Beverly (Pixie) Hobby from Surrey, a former NDP candidate. One from the eight ridings of Fraser Valley-Langley such as Abbotsford’s Aird Flavelle or Langley’s Cheryl Wiens. Two more from Vancouver Island like Victoria school trustee Nicole Duncan, Annemieke Holthuis or Jenn Neilson in Victoria, or Chris Istace from North Cowichan, two from the Interior (see above) and one from the North (see above).
Why do the Greens get only 13 MLAs? Province-wide, they might deserve 13.59, while the Liberals deserve 30.43. But the Liberals do better in the North which is over-represented to give sparsely populated areas and indigenous minorities fair representation, while the Greens ran only four candidates in those ten ridings, giving a slight edge to the Liberals. This MMP model has 52 local MLAs, and 35 regional MLAs for top-up seats.
Who would be the government?
The projected result is 43 NDP, 31 Liberals, 13 Greens. With the NDP one short of a majority, I assume the NDP would have continued to govern with a confidence and support agreement with the Greens, as they did since 2017. A coalition government might be even better, but many Green MLAs say they will not be bound to vote along party lines, making it difficult for them to be part of a government whose measures have to be sustained by a majority of MLAs for four years. (They did vote confidence in the NDP government from 2017 to 2020, but that's not quite the same thing.) A Liberal-Green coalition government would not likely be workable.
What about the BC Conservatives?
The BC Conservative Party ran only 19 candidates in the 87 ridings, so they got only 1.9% of the vote, but at that rate a full slate would have gotten 8.7%. Furthermore, to repeat, when every vote counts, voters won't have to worry about splitting the vote, or casting a strategic vote. So the BC Conservatives would have cast enough votes to elect some MLAs. Even with the few votes cast for those 19, if you ignore the threshold they got enough votes to elect their leader Trevor Bolin in the North, one in the Interior like party Vice-President Darryl Seres in Osoyoos or Kyle Delfing in Vernon, and one in Fraser Valley-Langley like former Liberal Diane Janzen in Chiliwack or party past-President Ryan Warawa in Langley.
Why think about proportional representation in BC after the referendum outcome?
Polling evidence is clear: A simple pro-rep question could have won. It's clear that some potential supporters voted against PR because they did not feel informed enough, or perceived the whole process unacceptable, or found the options unclear or unconvincing, or found the questions confusing, or feared MLAs being appointed from party lists, or they were just afraid to vote for "the mystery box.” The survey shows that large majorities of British Columbians support basic PR concepts. More details here.