Referendum may be needed to limit number of TDs in Dáil

If current population trends continue Dáil could have as many as 250 TDs by mid-century

Ireland could have 250 TDs by the middle of the century unless there is a referendum to increase the current 30,000 population limit for each Dáil member, political scientists have said.

The next Dáil will be the largest ever because of a significant spike in population over the last five years. There are now more than 5 million people in the country, the largest population since the foundation of the State.

Article 16 of the Constitution specifies that there must be one TD for between 20,000 and 30,000 of the population. However, preliminary figures from Census 2022 show that the number of people for each TD has risen to 32,022.

Limerick County is now the only one of the 39 Dáil constituencies that has less than 30,000 people per TD.


The first task of the newly-established Electoral Commission later this spring will be to redraw constituencies to accommodate the significant increase in population. As a consequence of that change the next Dáil will have between 171 and 181 seats, an increase of between 11 and 21 on the current number of TDs.

Until recent years the figures were close to the lower limit of 20,000, but the rapid rise in population over the past 15 years has seen the upper limit of 30,000 being broken in each referendum.

If the population continues to increase at a rate of 2 per cent annually the rules will mean that 15 new TDs will be added to the Dáil every five years if the constitutional limits are not to be breached. By comparison, the Westminster parliament has one MP for every 92,000 people, some three times higher than the Irish ratio.

Leading political scientists have said that if the population continues to increase this issue will have to be dealt with by way of a constitutional amendment otherwise the Dáil will become too large.

David Farrell, professor of politics at University College Dublin, said that until now the Dáil has tended to be on par with the size to be expected per population.

He said there was a cube root rule, devised by the Estonian political scientist Rein Taagepera. “As the cube root rule shows, the relationship between population and parliament size is curvilinear. As population rises the size of a parliament should increase at a relatively slower rate.”

He said that if our current constitutional rule produced a significantly larger Dáil then Ireland would no longer fit on that curve. and would have more representatives per population than most other countries. “Clearly the game-changer is our relatively recent experience of dramatic population growth. Our 1937-derived rule no longer fits. I agree that we need to consider a constitutional change to take account of a scenario where our population is growing (something unheard of in 1937).”

Prof Gary Murphy, professor of politics at Dublin City University, agreed that the phenomenon will need to be addressed at some stage. “Unless a referendum is held to limit the numbers we will have a Dáil with well over 200 members, the consequence of which will be unknown but could lead to some volatility.”

A spokeswoman for Minister for Housing and Local Government Darragh O’Brien said the provisions of the Electoral Reform Act 2022 will enable the Electoral Commission to conduct research on electoral policy and procedure. She said it will have the power to make recommendations to the Minister and Government as it considers appropriate. “The commission will be well placed to carry out that research and make recommendations on such an issue (as the size of the Dáil compared to population size),” she said.

Harry McGee

Harry McGee

Harry McGee is a Political Correspondent with The Irish Times