Based on Peeters' behavioural-adaptive model which posits that biases in trait attribution serve to avert potential harm to the individual, this study tested the hypothesis that the evidentiary standards for inferring warmth-related traits are affected by the competence of the target being judged. As incorrectly ascribing warmth to a highly competent target is potentially more harmful than incorrectly ascribing warmth to an incompetent target, I expected higher confirmation and lower disconfirmation thresholds for positive warmth-related traits and lower confirmation and higher disconfirmation thresholds for negative warmth-related traits for competent as opposed to incompetent targets. The hypotheses were confirmed for positive, but not for negative traits. The effect of target competence on instances confirming (but not instances disconfirming) ratings was mediated by differences in the potential harmfulness of making incorrect trait attributions. An alternative explanation for these findings, namely that different expectancies for competent versus incompetent targets can account for differences in (dis-) confirmation thresholds, was ruled out. The implications of these findings for interpersonal relations and group stereotypes are discussed. Copyright © 2008 John Wiley & Sons, Ltd.