The cases had all been reported to the Detroit Police Department in 1989. The sample included only cases presented to the warrant section of the Wayne County (Mich.) Prosecutor's Office for a decision to file charges. The analysis included six case characteristics and eight victim characteristics and controlled for four evidence factors. Results revealed that prosecutors were much more likely to file charges if the victim was an adolescent or an adult rather than a child. Charging was also affected by the victim's moral character and her behavior at the time of the incident. Moreover, these victim characteristics influenced charging regardless of the strength of the evidence in the case or whether the crime was classified as an aggravated or a simple sexual assault. Overall, findings suggested that Detroit prosecutors regard victim characteristics as relevant to convictability in all types of sexual assault cases. Findings also suggested that prosecutors attempted to avoid uncertainty by screening out sexual assault cases unlikely to result in a conviction because of questions about the victim's character, the victim's behavior at the time of the incident, and the victim's credibility. Tables, footnotes, case citation, statute citation, and 58 references (Author abstract modified)