A number of researchers have begun to demonstrate that the widely discussed ‘Knobe effect’ (wherein participants are more likely to think that actions with bad side-effects are brought about intentionally than actions with good or neutral side-effects) can be found in theory of mind judgments that do not involve the concept of intentional action. In this article we report experimental results that show that attributions of knowledge can be influenced by the kinds of (non-epistemic) concerns that drive the Knobe effect. Our findings suggest there is good reason to think that the epistemic version of the Knobe effect is a theoretically significant and robust effect and that the goodness or badness of side-effects can often have greater influence on participant knowledge attributions than explicit information about objective probabilities. Thus, our work sheds light on important ways in which participant assessments of actions can affect the epistemic assessments participants make of agents’ beliefs. keywords: Knobe effect, experimental epistemology, knowledge attribution, folk psychology...