Many voters would have forgiven David Cameron if he had failed to deliver on his campaign promise to hold an EU referendum, a study suggests.
Mr Cameron would not have been seen as less competent by the electorate if he had failed to give them a say on Britain's EU membership, according to the University of Exeter research funded by the Economic and Social Research Council.
Just 28 per cent of people questioned in a survey said their view of Mr Cameron would have been significantly diminished if he hadn't held the referendum, while 70 per cent said his reputation would have been untarnished.
The results suggest Mr Cameron could have effectively justified a decision to not go ahead with the referendum by citing internal or external political pressures - the survey found 30 per cent of participants would not have thought of him as less competent if he had put forward those reasons.
Dr Catarina Thomson, a member of the research team, said: "Failed promises, backing down on threats or flip-flopping on policy positions are often assumed to lead to a loss in support. But in the case of David Cameron, going back on his campaign promises meant this loss could have been manageable."
The experts conducted a survey just after the 2015 UK general election, almost six months before the EU Referendum Act was approved in the House of Lords, to test people's responses to a scenario put to them where Mr Cameron didn't go ahead with the referendum.
The results show that less than 30 per cent of participants would not have approved of the decision, regardless of the justification used to not hold the referendum.
Dr Gabriel Katz, another member of the research team, said: "Although it is impossible to know what the actual effects might have been, how Cameron's Eurosceptic backbenchers would have reacted or whether the government could have successfully managed to control how backing down was framed, the immediate political costs might not have been necessarily substantial.
"Choosing to hold the referendum ultimately cost Cameron his job, but our main finding is simple: had Cameron backed down from his campaign pledge to carry out the EU referendum, the costs might have been manageable."
Professor Dan Stevens, from the research team, said: "The results of our study suggest governments can mitigate the risk of going back on their promises if they are able to justify why they have done so, especially when the blame can be placed on factors outside their control."
Dr Travis Coan, also part of the team, added that, "Our results do indicate that had the external pressure justification remained part of the discourse, the negative impacts might have been mitigated."
The survey was carried out online with 1,830 British citizens drawn from 571 constituencies throughout England, Scotland and Wales. They were asked about their class, political identification, media consumption habits, political knowledge, attitudes towards immigration and party identification.
A control group was told that the pledge to hold an EU referendum would likely be honoured as promised, while people in three other groups were told the new government was likely to renege on the party's campaign promise. Participants in one of these three groups were given information which blamed the internal political opposition faced by the Tories. Another group were told the reason was because of external opposition, and that the vote was unlikely to be held due to the strong objections of other EU members. A third had information blaming the new government, explaining that it did not intend to hold the referendum and that the pledge was seen as an attempt to attract potential UKIP voters before the election.
All participants were then asked if they approved of the action David Cameron was about to take, and their assessment of this competence. Their responses were coded on an 11 point scale.
A little justification goes a long way: audience costs and the EU referendum is published in the International Journal of Political Science.