Bridging the Perception Gap in Parliament: UK MPs underestimate climate policy support and overestimate polarisation.

This study tested whether Members of Parliament (MPs) in the United Kingdom misread public support for climate policies and whether this perception gap can be corrected. Given MPs’ central role in shaping policy direction, underestimation of public support for climate action could carry serious consequences for climate progress and for representative democracy, but remains understudied. In an online survey–experiment with current MPs (N=100), participants’ estimated support for four climate policies under both neutral and cost-salient descriptions were compared with nationally representative polling. MPs significantly underestimated public support, and underestimated public willingness to accept financial impacts of climate policies. This study also offered novel evidence that MPs exaggerated partisan polarisation and formed significantly larger underestimation of support among Conservative voters. Offering original evidence of Spiral of Silence in Parliament, lower perceived support was associated with lower willingness to advocate for a pricing policy. Results indicated significantly larger underestimation of public support in politicians opposed to a climate policy, but even supportive politicians underestimate on average. Bayesian estimation suggested a moderate effect of a norm-based intervention on underestimation reduction, although results were inconclusive under frequentist tests. These findings suggest that misperceptions of others’ preferences within Parliament are structured in a way that can actively discourage climate advocacy, by presenting public opinion on climate policy as weaker and more polarised than it is. By highlighting gaps between public demand and elite perception, the study identifies a tractable barrier to climate action and democratic responsiveness.