Just Use MMP

One word describes the outcome of England’s latest local elections: fragmented. In some places, things were so bad that candidates won a seat on barely one-fifth of the vote. For instance, in one ward in Birmingham, the winning candidate won on just 20.5% of the vote. This continued an ongoing trend in British politics, with the 2024 General Election having also been the most fragmented in the nation’s history.

Bluntly, the UK’s first-past-the-post electoral system is not built for this. And even if the electoral realities force the parties to coalesce into coherent blocs, effectively reconstituting a two-party system, as Robert Shrimsley has suggested, the problem will still not go away. Fragmentation is not some errant phenomenon: it’s an outcome of our ongoing dealignment. Voters’ partisan attachments are weaker than ever before; hence, they are more prone to switch from party to party. So, even if two new large party blocs did emerge, there’s nothing to stop new parties from emerging again. In essence, voters want choices, and that will not go away.

My view is that the UK should scrap first-past-the-post and adopt proportional representation. Personally, I would prefer closed list proportional representation like we used to use for our elections to the European Parliament. But I don’t think that will happen, since it’s too far removed from the system that we already have (and that our parliamentarians are used to). So, I think the UK should just go for Mixed-Member Proportional Representation since we can implement it by simply extending what we’ve already got.

Under MMP, voters vote twice: once for the candidate they want to represent them in their district and once for the party they want to represent them in their region or nation. The system then allocates members in districts using first-past-the-post, then tops them up with members from the party lists to make the result more proportional. The reason I think that MMP is the strategically most sensible route to PR is that it is achievable simply by tacking a list system onto what we already have.

The one downside is that it would mean dividing existing seats into district and list members. That means that some MPs who represent inner cities might see the already massive populations that they represent double overnight. But this is not insurmountable. As I said on Bluesky earlier today, the new settlement would also require that we better fund MPs’ offices, which is not much of a price to pay for better politics.

So what would this look like in practice? If we assume that the constituency-level results would have been the same in 2024 under PR and use constituency votes aggregated to the region level as a stand-in for our list tier, we can get a rough idea of what the result might have looked like under MMP. In this simulation, parties outside the main set shown below are omitted from the list tier. The interactive below presents the results, along with my normalised version of the Gallagher index of disproportionality. By adjusting the slider, you can see the impact that altering the balance between district and list MPs has on the result.

MMP Simulator

District

316

List

316

Disproportionality

0.6/100

Party	List vote	District	List	Total	Seats
Labour	36.6%	209	25	234
Conservative	25.1%	60	98	158
Reform UK	15.2%	2	94	96
Liberal Democrat	12.6%	36	42	78
Green	7.3%	1	43	44
SNP	2.5%	4	12	16
Plaid Cymru	0.7%	2	2	4
Independent	0.0%	2	0	2

Note: District results may not replicate the 2024 election exactly, as this simulation is based on regional top-ups and reallocates seats within regions using the largest remainder method.

As the disproportionality figure makes clear: we can get a lot closer to more inclusive elections if we add list seats into the mix. Importantly, under MMP this does not require abandoning local representation. So, while it may not be my ideal electoral system, and would still involve real trade-offs, it is proportional representation by the most plausible route possible: keep the constituency link, add a regional list tier, and stop pretending that first-past-the-post can cope with a fragmented electorate.