On strategic choices

Christopher Kam's series of posts on political parties' strategy surrounding electoral reform is definitely worth a read. But I'll stand by the view that there's another alternative interpretation of the likely outcomes - particularly based on the likely alignment of any coalition between parties:

The configuration of parties’ preference orderings over electoral systems suggests two nascent coalitions**:

1. An ideological coalition of the Liberals, NDP, and Greens versus the Conservatives;
2. A coalition of the large (Liberals and Conservatives) against the small (NDP and Greens).

The first coalition could come together around a high-district magnitude STV system, but not around MMP. The second could come together around AV or low-M STV.

Frankly, I just don’t see the first coalition as all that viable. Here’s why:

1. The Liberals enjoy a majority; they can impose their own choice on the country;
2. The Liberals are also the only party that’s common to both coalitions; quite apart from their majority, they are pivotal on this issue;
3. The Conservatives actually have some leverage vis-a-vis the Liberals in the form of a (temporary) Senate majority. Even if the Liberals were to stack the Senate, the Conservatives could mount a fairly effective blockade of the legislation.
4. Let’s say that the first coalition threatens to crystallize around high-M STV (or, due to some surprising event, around MMP), the Conservative could concede AV to the Liberals.  This offer i) gets the Liberals exactly what they want with ii) the support of their main ideological opponent (all the better to rebut charges of self-interest), and iii) AV’s district magnitude of 1 preserves the disproportionality that that Conservatives need to do well; and iv) it removes electoral reform from the agenda for decades.
5. To repeat, MMP just doesn’t serve the Liberals’ interests as well as AV or low-M STV.

For these reasons (and especially the last), a coalition of the Large versus the Small seems more likely to me.

Now, it's certainly possible that the parties' decision-making could reflect Kam's theoretical analysis. But even leaving aside the points I've made as to how the Cons may have some incentive of their own to prefer a more proportional system, there's also reason to think the "ideological coalition" may have more legs than Kam thinks.

As Frank Graves for one has repeatedly pointed out, the Libs' election victory was based largely on support from exactly that coalition: the decisive group of voters was one of "promiscuous progressives" who had relatively little preference as to which party took power so long as it replaced the Cons. And indeed, it remains the case that the NDP and Thomas Mulcair are seen positively - just not as much so as the party basking in the glow of winning power.

From that starting point, there would seem to be no more sure way to lose the approval of many of the voters who put the Libs in power than by breaking a clear election promise, giving in to the demands of the Cons, and perpetuating the system which allowed Stephen Harper to win majority power with minority support. In other words, there's an obvious practical reason why first-past-the-post should be taken off the table.

Kam raises the possibility that the Cons and Libs might instead agree on AV as an alternative. But that analysis leaves out the possibility that the Cons might not play along - meaning the Libs would have the choice of going it alone on AV and facing attacks on all sides, or seeking common ground on MMP or other more proportional systems.

And even if the Cons are willing to participate in a "Large" coalition backing AV, there's still significant political risk in acting with their support alone.

That type of insiders vs. outsiders dynamic can be exactly what an outsider party needs to boost its support beyond what's previously been seen as possible, particularly if the Libs' cooperation with the Cons alone is seen to disqualify them as "progressive". And an AV election where voters inclined toward the NDP, Greens and Bloc all find common ground in disapproving of the Libs' choice of electoral systems might result in some highly unpleasant surprises for Trudeau.

One can fairly make the argument that the factors mentioned by Kam will still win out in the end. But if they do, it's not for lack of some significant countervailing forces - and the Libs will want to be careful how much they feed into an argument that they're merely reinforcing what they've promised to replace.