Despite our optimistic belief that we would behave honestly when facing the temptation to act unethically, we often cross ethical boundaries. This paper explores one possibility of why people engage in unethical behavior over time by suggesting that their memory for their past unethical actions is impaired. We propose that, after engaging in unethical behavior, individuals' memories of their actions become more obfuscated over time because of the psychological distress and discomfort such misdeeds cause. In nine studies (n = 2,109), we show that engaging in unethical behavior produces changes in memory so that memories of unethical actions gradually become less clear and vivid than memories of ethical actions or other types of actions that are either positive or negative in valence. We term this memory obfuscation of one's unethical acts over time "unethical amnesia." Because of unethical amnesia, people are more likely to act dishonestly repeatedly over time.dishonesty | memory | unethical behavior | psychological dissonance | morality A cross the globe, dishonesty is a widespread and common phenomenon. On an all-too-regular basis, the news reports cases of ethical misconduct in business, politics, sports, education, and medicine, behaviors that cost society millions, possibly billions, of dollars every year. Although certainly worrisome, these actions account for only a small portion of the dishonesty present in societies across the globe. Many people who consider themselves honest nevertheless often cheat on taxes, steal from the workplace, illegally download music from the internet, have extramarital affairs, use public transportation for free, lie, and so on. The costs of such arguably small-scale dishonesty are surprisingly large, both socially and financially.These troubling data explain, at least in part, why scholars across disciplines ranging from law and economics to psychology and management have become increasingly interested in studying when and why people, even those who report that they value morality, often act unethically (1). To date, this research has focused largely on identifying situational pressures that can sway a person's moral compass (2) and on examining how individual differences predict various forms of unethical behavior (3).Despite the many insights such work has provided, we still know little about why people engage in unethical behavior repeatedly over time. Because dishonesty often results in guilt, remorse, or other negative emotions (4), we might expect that people would avoid continuing to act unethically. However, anecdotal evidence across the domains highlighted earlier suggests just the opposite. Here, we identify one possible reason for persistent dishonesty: Unethical actions tend to be forgotten; when remembered, memories of unethical behavior become less clear and vivid over time than those of ethical actions or other types of positive and negative behaviors.Despite the common belief people hold that they are more ethical and fairer than others (5) and their strong de...