Lying is sometimes ethical, but honesty is the best policy: The desire to avoid harmful lies leads to moral preferences for unconditional honesty.

People believe that some lies are ethical, while also claiming that "honesty is the best policy." In this article, we introduce a theory to explain this apparent inconsistency. Even though people view prosocial lies as ethical, they believe it is more important-and more moral-to avoid harmful lies than to allow prosocial lies. Unconditional honesty (simply telling the truth, without finding out how honesty will affect others) is therefore seen as ethical because it prevents the most unethical actions (i.e., harmful lies) from occurring, even though it does not optimize every moral decision. We test this theory across five focal experiments and 10 supplemental studies. Consistent with our account, we find that communicators who tell the truth without finding out how honesty will affect others are viewed as more ethical, and are trusted more, than communicators who look for information about the social consequences of honesty before communicating. However, the moral preference for unconditional honesty attenuates when it is certain that looking for more information will not lead to harmful lies. Overall, this research provides a holistic understanding of how people think about honesty and suggests that moral rules are not valued because people believe all rule violations are wrong, but rather, because they believe some violations must be avoided entirely. (PsycInfo Database Record (c) 2024 APA, all rights reserved).