Research about intoxicated witnesses and criminal suspects is surprisingly limited, considering the police believe that they are quite ubiquitous. In the present study, we assessed the involvement of intoxicated witnesses and suspects in the investigation of rape, robbery, and assault crimes by analyzing cases that were referred by the police to a prosecutor’s office. Results indicated that intoxicated witnesses and suspects played an appreciable role in criminal investigations: Intoxicated witnesses were just as likely as sober ones to provide a description of the culprit and to take an identification test, suggesting criminal investigators treat intoxicated and sober witnesses similarly. Moreover, intoxicated suspects typically admitted to the police that they had consumed alcohol and/or drugs, and they were usually arrested on the same day as the crime. This archival analysis highlights the many ways in which alcohol impacts testimony during criminal investigations and underscores the need for additional research to investigate best practices for obtaining testimony from intoxicated witnesses and suspects.