A crisis is a decisive moment that can provide an opportunity for a change, but also reaffirm power asymmetries. This conceptual article highlights the Janus-faced character of declaring a climate emergency. More than 2,300 municipalities worldwide have done so. On the one hand, climate crisis and emergency narratives imply a disruption in which the dominant economic system is collectively challenged, enabling citizens to exercise power with others for greater sustainability. On the other hand, climate knowledge is often perceived as conclusive, paving the way for greater power over citizens and towards authoritarianism.