Just the Grim Sleeper Serial Killer

Just the Grim Sleeper Serial Killer

Original Release Date: December 4, 2020

In episode five of the 2020 Case Studies season, Just Science sat down with Rockne Harmon, forensic consultant and former senior deputy district attorney for Alameda County in California, to talk about familial DNA searching and the case of the Grim Sleeper Serial Killer.

From the mid 80s to 2007, Lonnie David Franklin Jr, otherwise known as the Grim Sleeper, was responsible for at least 10 murders in California. Although he started killing in the 1980s, large gaps of time between murders and underutilized DNA evidence left at the crime scenes made it exceptionally difficult to find a suspect.

Franklin was arrested in 2010 after investigators used familial DNA searching to connect DNA recovered at multiple crime scenes to one of Franklin's relatives. Rockne Harmon was instrumental in convincing the California Department of Justice to implement familial DNA searching in cold cases, ultimately leading to the arrest of the Grim Sleeper and many other offenders. Listen along as he discusses familial DNA searching and the case of the Grim Sleeper in this episode of Just Science.

This episode of Just Science is funded by the National Institute of Justice’s Forensic Technology Center of Excellence [Award 2016-MU-BX-K110].

Listen to or download the episode here:

Guest Biography

Rockne P. Harmon is currently employed as a consultant to numerous law enforcement agencies dealing with such issues as cold case investigation and other issues related to forensic DNA typing. He is currently an Instructor at U.C. Davis in the Masters in Forensic Science program. He retired in 2007 after a 33-year career as a Senior Deputy District Attorney for Alameda County, California. He graduated from the United States Naval Academy in 1967 and served four years active duty. He served a combat tour in Vietnam as Officer in Charge of a Navy Swift Boat and received the Purple Heart for wounds received in combat. After his military service he attended the University of San Francisco School of Law and graduated in 1974. He is a Fellow of the American Academy of Forensic Sciences. He was the Chairman of the California District Attorneys' Association Forensic Science Committee and was on the Advisory Board to the International Homicide Investigators' Association for many years. At Alameda County he developed a highly successful protocol for solving old or unsolved cases using DNA typing. He was the driving force behind the California Attorney General's decision to implement familial DNA searching in California that led to the arrest of the "Grim Sleeper" serial killer in 2010.

The opinions, findings, and conclusions or recommendations expressed in this podcast episode are those of the presenter(s) and do not necessarily reflect those of the U.S. Department of Justice.

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