In this week’s episode of "Zone 7," Sheryl McCollum talks with author and investigative reporter Casey Sherman about the murder of his aunt, Mary Sullivan, long believed to be the final victim of the Boston Strangler, and the lasting impact her murder had on his family.

Casey explains why his family has long questioned the official story, pointing to evidence that, in his view, complicates what many people think they know about the case.

Their conversation touches on DNA analysis, missing confession tapes, and alternate suspects that Casey believes raise serious questions about Albert DeSalvo’s role in the murders.

Guest Bio

Casey Sherman is a New York Times bestselling-author and investigative reporter known for revisiting major crimes and historic tragedies.

He is the author of  "A Rose for Mary," which examines the murder of his aunt, Mary Sullivan, and the lingering questions surrounding the Boston Strangler case.

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 case include, in part, The Boston Strangler, Natalie Holloway, and Tupac Shakur. McCollum’s work on 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:

Email: coldcase2004@gmail.com

X: @zone7squad

Facebook: @sheryl.mccollum

Instagram: @officialzone7podcast

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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 opens with the DNA dispute at the center of the Boston Strangler case

(1:30) Sheryl welcomes Casey Sherman and explains why his work has changed how she views the case

(7:15) Casey explains how Mary Sullivan’s murder shaped his family for generations and why his mother never accepted the official story

(9:15) The missing confession tapes and the details that convinced Casey the official story didn’t hold up

(11:30) Missing evidence, stolen case materials, and the long-term damage they can do to a major investigation

(14:00) The DNA evidence Case says pointed to a prime suspect from 1964 and how that lead eventually took him to a golf course in northern New England

(16:30) Why Casey believes the Boston Strangler case was not the work of one man and that similar killings stretched across multiple states

(19:30) How sensational crime coverage in the 1960s may have helped shape false confessions

(21:15) Casey’s theory that George Nassar may have helped feed DeSalvo information and why DeSalvo was never charged with the murders he confessed to

(24:15) Casey on the pressure surrounding the case and why he believes too many important questions are still unanswered

(27:45) F. Lee Bailey’s role in the case and the unlikely friendship that followed years later

(31:30) The importance of revisiting evidence and challenging the accepted story