New study examines the influence and impact of conspiracy theories surrounding the death of Princess Diana

In their forthcoming paper, "The hidden impact of conspiracy theories: Perceived and actual influence of theories surrounding the death of Princess Diana", Dr Karen Douglas and Dr Robbie Sutton from the University of Kent show that people are persuaded by conspiracy theories about Princess Diana’s death even though they do not necessarily know it.

In their study, which is to be published in the Journal of Social Psychology, the authors find that while people accurately judge the extent to which others are influenced by conspiracy theories, they are unaware of the extent to which their own attitudes have changed – a change that may actually serve to perpetuate the theories.

After reading internet-based conspiracy theories about the death of Princess Diana, research participants agreed more strongly with statements such as ‘there was an official campaign by MI6 to assassinate Diana, sanctioned by elements of the establishment’. When asked how much they would have agreed with those statements prior to reading the conspiracy theories, they ‘revised’ their prior attitudes so that they were closer to their current attitudes – this made it appear as though their attitudes had changed less than they actually had.

Dr Douglas said: ‘Our research provides a first psychological examination of the impact of conspiracy theories. It also provides a potential explanation for an interesting paradox. Why do conspiracy theories endure when there is no factual support for them, and even when they fly in the face of established facts? Our findings suggest that conspiracy theories may actually have a ‘hidden impact’, meaning that they powerfully influence people’s attitudes whilst people do not know it; outwardly they may deny the extent to which they have been influenced but in truth they tend to endorse the new information and pass it on to others.’

These findings echo previous work by the authors which shows that people are also persuaded by pro-gun, pro-fossil fuel and anti-fossil fuel arguments but without the awareness that their attitudes have changed.