People react as Ireland voted in favour of allowing same-sex marriage in a historic referendum, in Dublin May 23, 2015. Ireland became the first country in the world to adopt same-sex marriage by popular vote as 62 percent of the electorate backed a referendum, official results showed on Saturday. REUTERS/Cathal McNaughton

On May 22, the citizens of Ireland voted to broaden the definition of marriage in the constitution and provide for marriage equality. The referendum was notable in a number of respects as discussed here, here and here. The referendum produced an exceptionally high level of turnout at 60.5 percent, and a majority of 62 percent voted in favor of the proposal. Average turnout at referendums in Ireland is just over 50 percent. Many observers saw this referendum as a major shift in Irish politics, marking the advent of a new, more socially liberal and more confident generation of young people.

We have carried out a referendum study based on survey data gathered by the Irish polling company Red C immediately after the referendum, and compared it to other data (gathered after the most recent general election in 2011). Our results confirm that conservative Ireland is dying a slow death. However, the key changes are not just a result of turnout among very young voters.

The referendum led to very high political engagement

The marriage referendum was a referendum on social policy. It resembled previous referendum votes on abortion, divorce and children’s rights. Historically, these types of referendums have highlighted stark divisions between conservatives and liberals. However, since the 1990s turnout at social policy referendums has been in decline and the last social policy referendum in 2012 recorded a turnout of just 33.5 percent. The 60.5 percent recorded for the marriage referendum was therefore all the more extraordinary.

This was likely in part the result of media campaigning. On polling day, there were extensive social media efforts to encourage people to vote. An impressive Facebook campaign reported real time demographic data on voters as tens of thousands took to the site to record their participation and their vote choice. Perhaps most interesting of all was the Twitter phenomenon of  #hometovote. The hashtag trended during the day and documented the efforts of thousands of Irish citizens living around the world as they traveled home to cast their votes. Ireland does not have provisions for emigrant voting. Both the widespread engagement with the referendum question and high youth turnout was similar in many respects to the September 2014 Scottish independence referendum.

Young people voted in large numbers – but didn’t make as big a difference as you might think

Many commentators noted the high level of participation among young voters. Increased participation by young voters was one of the most notable aspects of the referendum. Younger Irish voters, like their equivalents abroad, are less likely to vote than older voters. Those in the 18-24 age group are least likely to vote. There was strong anecdotal evidence in the lead-up to the referendum that young people were mobilized to vote. Media reports confirmed that nearly 60,000 additional voters had been added to the electoral register, increasing a total electorate of 3.1 million voters. Universities and colleges reported long lines of students waiting to complete their registration documentation leading to widespread speculation that a large percentage of the newly registered voters were young people.

Our data suggest that these anecdotal impressions were roughly correct. Turnout was reported to be 6 percent higher among 18 to 24 year olds in the marriage equality referendum than was true of the same age group in the 2011 general election. For other age groups, turnout was typically about 5 percent lower than in the election (see Figure 1). Thus, young people appear to have been more likely to vote than in everyday politics, and older people less likely to vote than usual.

However, this didn’t matter nearly as much for the final outcome as one might have expected. When we weight the survey respondents so that the ‘turnout’ for the different age groups matches the turnout that we saw in the 2011 general election, when youth participation was relatively depressed, we see a nearly identical prediction for the percentage of Yes votes. As Figure 2 (below) shows (in the green bars) a clear majority supports marriage equality in all but the oldest age groups. Marriage equality would almost certainly have been won in Ireland, even if young people hadn’t turned out in big numbers.

Young people didn’t know as much about the referendum as older people

In previous Irish referendums, it was usually possible to predict whether people would vote, and how they would vote, by asking how much they knew about the referendum issue. Irish voters generally avoid uncertain outcomes. “If you don’t know, vote no” and “If you don’t know, don’t vote” were common refrains from earlier campaigns. This obviously produces an incentive for No campaigners to confuse people and muddy the issues, so as to depress turnout and increase the No vote. However, it also means that those who know more about the issues are more likely to vote and more likely to vote yes.

This might lead one to expect that the young Yes voters should have had a good deal of correct knowledge about the issue. Younger people are more likely to be open about their own sexuality and to know someone in their social network who is gay or lesbian. Perhaps this increases their awareness of the issue? In Figure 3, we show the levels of knowledge of the referendum – evaluated by asking people in different age groups four factual questions about the referendum. Strikingly, the younger generation knows least.

Figure 3 suggests that this is largely a generational shift, rather than an effect of the stage in life of a voter. In other words, it is something specific to this generation of young people, rather than a stage that all young people go through. If we compare the marriage vote to the 1992 abortion referendums on whether Irish citizens have the freedom to travel to another country to get an abortion, and also on whether abortion information should be available in Ireland, we see that the cohort of those who were then 18-24 years old and are now 41-47, still votes more or less the same way.

The Irish marriage referendum therefore shows unusually high levels of mobilization and engagement among younger voters, but the impact on the result is very limited: had younger citizens not come out, the Yes side would still have easily won. This engagement also had its limitations: while younger voters did, indeed, come out to vote, they did not learn as much about the referendum issue as their older counterparts. Nevertheless, a generational shift is clearly visible in the survey data over time. Conservative Ireland is slowly dying.

Johan Elkink is a lecturer in politics and international relations at University College Dublin (@jelkink).

David Farrell is a professor of politics at University College Dublin (@dfarrell_ucd).

Jane Suiter is director of the Center for Future Media and Journalism at Dublin City University (@janesuit).

Theresa Reidy is a lecturer in politics at University College Cork (@theresareidy).