The LAPD’s most famous cold case, the Black Dahlia, has haunted headlines for generations, and a renewed wave of speculation now argues she was killed by the same person who later called himself the Zodiac. In this episode of "Zone 7," Sheryl McCollum is joined by forensic pathologist Dr. Priya Banerjee and forensic psychologist Dr. Joni Johnston to put that theory to the test. They argue Elizabeth Short’s murder reads as intimate and rage-driven, marked by postmortem mutilation and staging, while the Zodiac attacks appear cold and more mis...
The LAPD’s most famous cold case, the Black Dahlia, has haunted headlines for generations, and a renewed wave of speculation now argues she was killed by the same person who later called himself the Zodiac.
In this episode of "Zone 7," Sheryl McCollum is joined by forensic pathologist Dr. Priya Banerjee and forensic psychologist Dr. Joni Johnston to put that theory to the test.
They argue Elizabeth Short’s murder reads as intimate and rage-driven, marked by postmortem mutilation and staging, while the Zodiac attacks appear cold and more mission-oriented, closer to an execution than a personal assault.
They also clarify the difference between modus operandi and psychological signature, explain why signatures do not just “cool off” over decades, and urge civilians and investigators alike to test assumptions, scrutinize claims, and bring in smarter minds when the facts demand it.
Guest Bios:
Dr. Priya Banerjee is a board-certified forensic pathologist with extensive experience in death investigation, clinical forensics, and courtroom testimony. A John’s Hopkins graduate, she served for over a decade as Rhode Island’s state medical examiner and now leads a private forensic pathology practice.
Dr. Joni Johnston is a forensic psychologist, private investigator, and crime writer. Her work includes prison and parole settings, court-related forensic services, workplace misconduct investigations, parole evaluations for mentally disordered offenders, and expert testimony in criminal and civil cases.
About the Host
Sheryl “Mac” McCollum is an active crime scene investigator for a Metro Atlanta Police Department and the director of the Cold Case Investigative Research Institute, which partners with colleges and universities nationwide.
With more than 4 decades of experience, she has worked on thousands of cold cases using her investigative system, The Last 24/361, which integrates evidence, media, and advanced forensic testing.
Her work on high-profile cases, including the Boston Strangler, Natalie Holloway, Tupac Shakur and the Moore’s Ford Bridge lynching, led to her Emmy Award for "CSI: Atlanta" and induction into the National Law Enforcement Hall of Fame in 2023.
Social Links:
- X: @149Zone7
- Facebook: @sheryl.mccollum
- Instagram: @officialzone7podcast
- Email: coldcase2004@gmail.com
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Preorder Sheryl’s upcoming book, "Swans Don’t Swim in a Sewer: Lessons in Life, Justice, and Joy from a Forensic Scientist," releasing May 2026 from Simon and Schuster.
Highlights:
• (0:00) Sheryl McCollum frames the Black Dahlia and Zodiac question, and why “same killer” theories require disciplined testing
• (1:15) The Zodiac’s moniker, symbols, and ciphers as behavioral evidence through public messaging
• (2:45) Dr. Joni Johnston on why the Black Dahlia reads as personal, targeted violence rather than opportunistic killing
• (4:15) Modus operandi versus signature behavior, and where true crime narratives often blur the line
• (5:45) Antemortem versus postmortem behavior, and how that distinction changes scene interpretation
• (7:00) Why signature tends to remain stable over time, even when method or opportunity shifts
• (8:00) What autopsy findings and scene details can suggest about intent
• (15:00) Facial carving as humiliation, defacement, and control, and what that suggests about motive
• (18:15) Tattoo removal and insertion framed as symbolic degradation
• (20:15) Escalation narratives and control needs, testing patterns against a “same offender” theory
• (27:00) BTK comparison, and why taunting and offender messaging are not unique identifiers
• (31:45) Timeline gaps and intent differences as evidence against a single-offender theory
• (33:00) Closing quote and final takeaway on evidence, teamwork, and disciplined disagreement
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