Objective: The study was undertaken to better describe the assault characteristics and examination findings in sexual assault victims who pursue legal action. Study Design: A case-control study of consecutive women older than 15 years who came to an urban hospital after sexual assault over a 32-month period was conducted. All the women underwent a standardized history and physical examination by a resident in obstetrics and gynecology. Cases were those in which charges were filed against an assailant by the prosecutors' office. The controls were the women assaulted immediately preceding and after each case. Results: Of the 888 women undergoing evaluation in the emergency department, 132 (15%) had charges filed by the prosecutor. Characteristics positively associated with a legal outcome included being examined within 24 hours after assault, partner/spouse as an assailant, oral assault, and anogenital trauma (P < .05, .01, .05, .05, respectively). Amnesia at the time of assault and/or friend/acquaintance as assailant were negatively associated with a legal outcome (P < .01, .05, respectively). Conclusion: Although only 15% of sexual assault cases were resolved with a legal outcome, the data support the importance of a physical examination within 24 hours of the assault. Anogenital trauma is associated with, but not a prerequisite for, a successful legal outcome. (Am J Obstet Gynecol 2003;188:1638-41.)