A primary focus of research in the area of deceptive communication has been on people's ability to detect deception. The premise of the current paper is that participants in previous deception detection experiments may not have had access to the types of information people most often use to detect real-life lies. Further, deception detection experiments require that people make immediate judgements, although lie detection may occur over much longer spans of time. To test these speculations, respondents (N=202) were asked to recall an instance in which they had detected that another person had lied to them. They then answered open-ended questions concerning what the lie was about, who lied to them, and how they discovered the lie. The results suggest people most often rely on information from third parties and physical evidence when detecting lies, and that the detection of a lie is often a process that takes days, weeks, months, or longer. These findings challenge some commonly held assumptions about deception detection and have important implications for deception theory and research.