James Frayne is Director of Public First and author of Meet the People, a guide to moving public opinion.

Boris Johnson’s suggestion that a Conservative Government led by him would review the performance of so-called “sin taxes” was widely criticised. This is unsurprising; it has become almost universally accepted within Westminster, Whitehall and the media that such taxes are morally right and work well. A column in the FT yesterday even denied such taxes were regressive, by hitting the poorest hardest. We know what the political establishment thinks, but what do voters actually think about the issue?

Let’s look at what the polls tell us. I’m always surprised there hasn’t been more research on an issue the public takes a close interest in. There are only several recent polls in the public domain, rather than dozens. Depressingly for those that are sceptical about the merits of state action, overall, the polls tell a clear story: the public as a whole favours state intervention across a wide range of sectors. Inject the idea that state intervention is needed to protect children and the polling numbers rise even higher.

An Ipsos-Mori poll last year – to mark 70 years of the NHS – showed that “adults” (in this case, those 15+), showed that people clearly support the following: banning junk food ads on TV before 9pm, limiting fast food outlets near schools, restricting the advertising of unhealthy food and drink and a tax of sugary soft drinks. There is mild support both for banning e-cigarettes in public spaces and a minimum price for alcohol.

A YouGov poll for Cancer Research from a year ago showed much the same. By 66% to 23%, people said they supported “Government passing laws to make sure supermarkets promote healthier options”, and by 73% to 18%, people said they supported “Government passing laws to make sure the food and drinks industry reduces the amount of sugar and fat in their foods”. Another YouGov poll from last year (I can’t work out the client) also showed similar levels of public support for Government action.

There are, as ever, some caveats to attach to these results. The first is that people still fundamentally think individuals are responsible for their own health. In Ipsos-Mori’s poll, when asked who had most responsibility for people staying healthy, respondents overwhelmingly said “the individual”. 97% of people said individuals had a great deal or a fair amount of responsibility for their own health, compared to 75% who said the food and drinks industry and 61% who said the Government. A Delta poll for my agency, Public First, showed that while people back a range of options to help deal with childhood obesity, they hold parents primarily responsible for the health of their children.

An additional caveat is that Ipsos-Mori’s poll showed significant class differences over the support for different policies. Boiled down, professionals from an “AB” background are much more likely to support action than those from a C2/D/E background – although less affluent voters are also likely to support state intervention too. The same is generally true of the other polls highlighted above. The FT article I note above denies these taxes are regressive, but the polls suggest less affluent people disagree (although we can’t be sure that’s why they’re more sceptical, to be fair).

On the prospect of state action, things could not be any clearer. Or could they? I write about opinion research on this site all the time and I am clearly no research sceptic. That said, top line polls don’t always tell us the full story – and there are three problems with the “meaning” deriving from the existing research, which warrants further exploration. Firstly, and most importantly, the polls don’t offer either compelling negative counter arguments, nor do they offer intelligent alternatives to state action. The polls are generally tests of positive arguments for state action – and such polls invariably drive positive responses.

Related to this, secondly, they generally don’t make people think about cost. It’s one thing to give support to abstract policy ideas that might affect others, but another for them to actively support significantly higher shopping bills. Few polls really make people think hard about cost implications.

Thirdly, most of these polls, by probing people’s straightforward reaction to a list of suggestions, don’t measure how important people think policies actually are. For example, questions that test people’s attitudes towards ad restrictions usually score highly because people don’t think they are personally susceptible to advertising, while thinking that children might be. It’s therefore easy for them to say they think ads should be restricted. But when I’ve asked people in the past to choose which policies, from a list of measures, would be most effective in dealing with a problem like obesity, restricting advertising usually falls towards the bottom.

There is a further complication to consider: the fact that there are very few public voices against state action. Free market think tanks – most obviously, the IEA under Christopher Snowdon’s excellent work – are the loudest and most persuasive voices. But, as they would readily admit, they don’t have the resources to take the battle to the public at large. Very few Conservative MPs are willing to take on this battle, and the food and drink industry can’t be bothered to make the case themselves, mostly preferring to attend pointless roundtables with Government instead of defending their position to the public. (I once attended an event where a marketing person from a food manufacturer proudly described how the Health Minister of the time had attended the launch of their newly-reformulated product, only then mentioning in passing that the product was likely to be discontinued because consumers hated it).

Together, all this means that we can’t really be sure what the public thinks about state action on unhealthy lifestyles. We only know what they think in the almost complete absence of counter arguments. As such, Boris Johnson’s review, should he ever have the time and space to deliver it, would likely be received by the public with more open-mindedness than people in Westminster, Whitehall and the media might expect.

(Full disclosure: my agency Public First has previously worked for clients in the food and drink sector and the alcohol sector.)