This Just Science podcast from the forensic case studies series sponsored by the National Institute of Justice consists of an interview with Ray Wickenheiser, who was involved with the crime lab's forensic examinations in the investigation of serial killings by Derrick Todd Lee, who targeted young women in the Baton Rouge area of Louisiana during the early 2000s.
Case issues discussed include the complex crime scenes of Lee's killings, with attention to the significance of a muddy footwear impression, a computer cord, and DNA evidence in contributing to Lee's arrest and conviction. Since all of the cases involved sexual assaults, Lee's DNA was obtained from his semen at the crime scenes, which showed a serial rapist/killer was involved. It also enabled investigators to conclude the killer was African-American. A muddy footprint at one of the crime scenes led to the identification of the type of shoe worn by the killer, but efforts to use this information to identify the killer were unsuccessful. The DNA information was eventually used to determine whether a rape case might exist in which the victim survived to identify the rapist. Such a case was found in which the DNA matched the serial rapist/killer and in which a computer cord was used to try and strangle the victim before he was interrupted and fled the scene with the computer cord still in his hand. It was subsequently identified as the same cord used to kill a subsequent victim. The living witness provided an identification of the offender that led to the development of a sketch of his features. This eventually led to a DNA match with a suspect who was interviewed based on similarity to the sketch based on a mug shot review.