This study abstracted data on 491 adult sexual assaults investigated by five large and midsized law enforcement agencies to describe the characteristics of sexual assault investigations and to explain the relationships between these characteristics and the likelihood that a suspect is arrested.
Sexual assault investigations present uniquely challenging circumstances to detectives, and a small proportion result in arrest. Improving sexual assault investigations requires expanding the evidence base to improve understanding of how these investigations unfold and the factors associated with positive case outcomes, including the likelihood that an offender is arrested. Overall, the findings of the current study indicate that detectives move swiftly to investigate sexual assaults but tend to miss investigative opportunities that increase the likelihood of an arrest, such as locating and processing the crime scene or pursuing interviews with key witnesses and leads. Sexual assaults typically lack physical evidence that can be used to identify and lead to an arrest of a suspected offender; when this evidence is present, the case is more likely to result in an arrest. Delayed reporting of the crime to law enforcement decreases the likelihood of a suspect being arrested, but the mechanisms are unclear. Few studies have used a detailed data abstraction process for a large sample of cases from multiple law enforcement agencies to understand sexual assault investigations and their case outcomes. The results of the current study can improve practitioners' and researchers' understanding of sexual assault investigations, including those factors that increase the likelihood of a suspect's arrest. (publisher abstract modified)