There are perennials of Irish political debate, and none more perennial than “We need to get rid of multi-seat constituencies” as the solution to all our political woes. If only we got rid of the “parish pump” competition at local level, we’d get a better standard of TD.

There’s also a growing body in the country who have latched on to the “nobody voted for this coalition government” argument, and are yearning for a British-style election result, where one party (usually) clearly wins regardless of how the actual people of that country actually vote. Nobody may have voted for this government, but they didn’t vote for any other one either.

It’ll never happen, of course. The Irish people have been asked twice before to change the voting system, and have refused for clear reason. PR-STV isn’t going anywhere: in fact, I suspect it would be next to impossible to even get the referendum bill past the Oireachtas, never mind win a referendum. The most a government might get away with is reducing the constituency seats to three seaters, which would hurt small parties and give larger parties a seat bonus.

But even that’s risky: FG/Lab tried the infamous “Tullymander” in the 1977 general election, and it rebounded on them spectacularly giving FF the biggest majority in Irish history.

But if it were to happen, what would be the outcome? It depends on the alternative system. The most popular system on the continent, a list system, where people vote for a party and it fills seats based on the share of the vote it gets from a list of candidates, is unlikely to be accepted here. Most Irish voters wants to vote for an individual.

As a result, the most likely options are First Past The Post (FPTP) or STV in single seat constituencies (also known as the Alternative Vote). Either would be a radical change, but both would have side effects which I suspect would not please advocates of change.

First Past the Post (FPTP) is the simplest voting system on Earth, a point its British advocates make a lot of noise about. Indeed, during the AV referendum in 2011, one of the main arguments used against the Irish electoral system was that it was too complicated for British voters. FPTP involves making a mark against a single candidate, and the most marks win. It allows a party to win a majority of the seats with a minority of the vote and is most likely to deliver a clear single party government even if a majority of the voters didn’t vote for it.  In 2005 it got Tony Blair a 60 seat majority despite 65% of voters not voting for him. Justin Trudeau got the most seats in the last two Canadian elections despite coming second to the Tories in votes. If you like your voting system to just vomit out results with occasionally a tangential link to how actual voters vote, FPTP is the one for you. It’s used in the UK, India, Canada, parts of the US and within some PR systems.

The Alternative Vote is used in Australia and is basically the same system we use in Ireland in presidential elections and  by-elections. It tends to create a de facto two-party system, as small parties rarely win seats, although their preferences do often decide the outcome, unlike FPTP.

Either system would be far less proportional than PRSTV, but it’s worth bearing in mind the role political culture would play hand in hand with either system. In the 1990s, hoping create a new more decisive political culture, Italy introduced FPTP for 75% of the seats in the lower house, with a 25% party list top-up. Whilst it did lead to some consolidation of parties, it also led to parties doing deals to stand down against each other in specific constituencies.

If Ireland switched to a single-seat system under either FPTP or AV, the number of constituencies would jump from 43 large ones currently to 168 much smaller ones (many the size of council wards), most with a nominal sitting deputy. But it would also open up a huge swathe of constituencies for parties that have no seat in them. For Sinn Fein and (probably) Fine Gael this would suit them, assuming they’d lead in many constituencies and would hope for transfers to get to the very high 50%+1 quota (under AV) or just the most votes under FPTP. For smaller parties, and I’m assuming FF in this (rightly or wrongly) there’d be a choice, be also-rans under FPTP or transfer fodder under AV. But there’d be alternatives too.

Under FPTP, FF, Labour, the Greens and the Social Democrats, all with sitting TDs, could form a pact and run a single “Alliance” candidate in each constituency, giving them a chance at least. It wouldn’t be easy: all four parties would have members with problems, but FPTP is unforgiving. Get your shit together or see your votes just be ignored, especially as SF and FG would both be telling those parties voters that they were wasting their votes or helping the other big party by voting for the alliance.

AV would offer a similar challenge, although without the vote wastage of FPTP. Given the need to reach 50% of the vote, it’s not impossible that the two big parties might be willing to do a deal with smaller parties, even standing down in some constituencies or promising Seanad seats in return for transfer endorsements. Both would actively need transfers unlike under FPTP. One issue with AV would be the challenge for SF to get transfers even if it has an impressive first preference lead nationally. It’s not impossible that, as happened to FF in the 2011 election, preferences keeping going against SF to the extent (and angry frustration of SF supporters) that SF loses seats narrowly to other parties despite having, in their eyes, clearly “won” the election in terms of having come first in votes.

Interestingly, both systems could seriously hurt the Alphabet Left who would struggle to reach the vote levels requires to come first or meet the quota.

Either system would make a single party government more likely, although AV would require much greater voter consent. Having said that, the backroom dealing that permeates Irish politics could still result in a tiny number of TDs holding even more power than they do now. After all, even if Kerry or Tipp were transformed into multiple single-seat constituencies, would you absolutely rule out Michael Lowry or the Healy-Raes taking some of them?