Quantitative weight of evidence information does not remove the impact of false balance

Even when subjects are given numerical information about the proportion of experts on either side of an issue, false balance has a distorting effect on message recipients. Kohler (2016) conducted two experiments on 402 US college students to determine whether false balance on given topic would influence whether they felt there was a consensus. This study found that the false balance effect was greater than any mitigating effect from weight of evidence information.

The sample was split into two groups - one of which was given just the numerical information about the proportion of experts on either side of an issue, and one of which was also given an explanation of their position from an expert on either side. Just by reading the explanation made people more likely to think there was a lack of consensus on an issue, even when they had the numerical data in front of them. Even worse, it even affected whether people thought the consensus was strong enough to use it to guide public policy decisions.


Journalistic balance is an important and useful aspect of most types of reporting. It helps to ensure that reporting is fair, impartial and represents all sides of a story. Most of the time it is highly appropriate to hear from experts on both sides of a contentious story. But in stories about scientifically verified facts, how far should journalists go to present other perspectives or information, when they are held by a small minority of dissenters?

"Everyone is entitled to his own opinion, but not to his own facts.” Former US senator Daniel Patrick Moynihan

One of the most obvious areas where balance is potentially unnecessary and often damaging is reporting on scientific topics.

If the body of science has shown something to be true, should people who claim it is not be included in a news report? What does a journalist do when writing a typical 'he said, she said' story, when only one side is telling the truth? Traditional journalistic ethics suggests that balance should always occur.

False balance often occurs in scientific areas like:

And perhaps nothing sums up the impact of false balance on climate change facts better than this:

The BBC has recently tried to provide some guidance on when balance is not required to avoid misinforming its audiences. This advice seems appropriate given the undue influence minority dissenting voices can have. It seems that the only way to ensure that a message recipient truly understands when there is a consensus of experts is to deny the small minority of dissenters their opportunity to provide comment in news stories reporting on scientific facts.

The ethics and practicalities of denying journalistic balance is fraught, but perhaps necessary to achieve greater societal advances in human development.

“There’s no other way to say it other than that, over 25 years it’s been a massive failure of journalism to communicate the idea to the public that the most dangerous thing that ever happened in the world is in the process of happening.” - US journalist, Bill McKibben

Of course false balance isn't just a problem for journalists and professional communicators - how on earth are people supposed to know which experts are right and which ones aren't? And that's an issue for us all.


  • Koehler, J. D. (2016). Can journalistic "false balance' distort public perception of consensus in expert opinion. Journal of Experimental Psychology Applied , 1-15.

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