Policy scholars tend to view disproportionate policy and its two component concepts – policy over- and underreaction – as either unintentional errors of commission or omission, or nonintentional responses that political executives never intended to implement yet are not executed unknowingly, inadvertently or accidentally. This article highlights a conceptual turn, whereby these concepts are reentering the policy lexicon as types of intentional policy responses that are largely undertaken when political executives are vulnerable to voters. Intentional overreactions derive from the desire of political executives to pander to voters’ opinions or signal extremity by overreacting to these opinions in domains susceptible to manipulation for credit-claiming purposes. Intentional underreactions are motivated by political executives’ attempts to avoid blame and may subsequently lead to deliberate overreaction. This conceptual turn forces scholars to recognise the political benefits that elected executives may reap from deliberately implementing disproportionate policies, and that such policies can at times be effective.

The literature on policy success and failure does not capture policies that may be too successful, as well as “too much” and/or “too soon” patterns of policy. To bridge this gap, this conceptual article relies on one of the most robust findings in the psychology of judgement, namely that many people are overconfident, prone to place too much faith in their intuitions. Based on this premise, the analytical framework advanced here revolves around two key dimensions of policy overreaction: (i) the effects of positive and negative events, and (ii) the effects of overestimation and accurate estimation of information. Based on these dimensions, the article identifies and illustrates four distinct modes of policy overreaction that reflect differences in the nature of implemented policy. It argues that the policy tools menu utilised in each mode of policy overreaction is dominated by unique mechanisms for changing or coordinating behaviour, which, once established, produce excessive – objective and/or perceived – social costs.