Background information for the interview notes that not all crime scenes will have bloodstains, but when they are present, analysts can use them to assist in determining the types of activities or mechanisms that produced the bloodstains. Erin Sims notes that bloodstain patterns can aid in understanding what occurred in the commission of the crime. In this interview, she discusses the application of bloodstain pattern analysis and its role in a crime-scene investigation. Most of the interview focuses on a case study in which she was a principal investigator. In this case, the surviving victim of a gunshot wound offered various differing accounts of how the shooting occurred, which required investigators to reconstruct what happened without the input of a truthful witness. Bloodstain analysis had a central role in the reconstruction of the shooting and the victim’s movements after the shooting.