Former prime minster Justin Trudeau infamously broke his promise to reform the electoral system. Trudeau’s own preference was for a type of majoritarian system called the Alternative Vote (AV) AKA Instant Runoff Voting (IRV). However, the House of Commons Special Committee on Electoral Reform established by his government went in a different direction: it ultimately recommended that the government design a system of proportional representation (PR) and vote on it through referendum.
Grossly, electoral systems are classified into majoritarian and proportional types. In addition to AV there are two other well-known majoritarian systems: FPTP and the two-round system (used in France). Trudeau rejected the recommendation to move away from a majoritarian system and has negatively characterized proportional representation in different ways. In this townhall exchange, Trudeau explains his opposition to PR. "If we were to make a change or risk a change that would augment individual voices — that would augment extremist voices and activist voices that don’t get to sit within a party that figures out what’s best for the whole future of the country, like the three existing parties do — I think we would be entering a period of instability and uncertainty."
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Political stability, dissatisfaction with democracy, and political polarization are easiest to compare with simple data. With political stability, PR countries on average perform better. With democratic dissatisfaction, PR countries dramatically outperform majoritarian countries. On political polarization, PR countries outperform, with Ireland achieving the lowest polarization score in the whole OECD.
Further, when you examine the three comparison pairings listed above, the PR country performs better on each dimension for all three pairs. Trudeau feared that proportional systems would bring instability, polarization, and that voices which undermine what’s good for the country would be augmented, but it’s the majoritarian countries where these concerns are more severe.
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Trudeau’s thesis was that these problematic outcomes should be happening in PR countries, not majoritarian ones. Given the observation we see, there is no basis to say that majoritarian electoral systems can minimize these concerns, there is simply no supporting evidence for this.
The idea that PR (at least the MMP and STV systems) would definitely lead to these outcomes is also not supported by the evidence. To be able claim that PR would cause extremism, or that majoritarian systems protect against, you would at least need to observe an association that suggests this possibility, but we do not observe any such association.
What we do have an association for is that MMP/STV are protective against democratic and social decay, while majoritarian countries inflame these issues, which is the opposite of what Trudeau believed. This does not mean causality, but it does make a causal relationship possible.
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In proportional systems, coalitions tend to form, and different political parties sharing power helps alleviate the irrational decision-making of groupthink in a majority government. In addition, politicians must always be wary about losing their spot at the top because voters can easily select alternative parties without the inhibitions of vote splitting and vote wasting. In a proportional system, there is no shielding to give a false sense of security: politicians understand that if they are complacent, a disruptive political force can easily swallow them, so they must stay vigilant and proactive about emerging political issues to keep the public satisfied. In proportional systems, complacency and corruption can be easily punished by the electorate, which keeps politicians disciplined.
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