Examining the Impact of Expert Voices: Communicating the Scientific Consensus on Genetically-modified Organisms

Scholars are divided over whether communicating to the public the existence of scientific consensus on an issue influences public acceptance of the conclusions represented by that consensus. Here, we examine the influence of four messages on perception and acceptance of the scientific consensus on the safety of genetically modified organisms (GMOs): two messages supporting the idea that there is a consensus that GMOs are safe for human consumption and two questioning that such a consensus exists. We found that although participants concluded that the pro-consensus messages made stronger arguments and were likely to be more representative of the scientific community's attitudes, those messages did not abate participants' concern about GMOs. In fact, people's pre-manipulation attitudes toward GMOs were the strongest predictor of of our outcome variables (i.e. perceived argument strength, post-message GMO concern, perception of what percent of scientists agree). Thus, the results of this study do not support the hypothesis that consensus messaging changes the public's hearts and minds, and provide more support, instead, for the strong role of motivated reasoning.