Can Psychology Help Solve a Murder Mystery? Analysis

“Justice commends our poisoned chalice to our own lips.” -- MacBeth

Posted Aug 10, 2020

The murder of Russell and Shirley Dermond, an elderly couple living in a gated lakefront community in rural Georgia, is now a cold case 6 years old.  The weird and unfathomable circumstances of their brutal demise were summarized in Part 1.  In this article, by applying psychological principles and theory to the available facts, I will  render observations and suggestions which may aid law enforcement.

The Dermond case is under the jurisdiction of Howard Sills, sheriff of Putnam County, Georgia.  As the case became more and more baffling for his department (and leads became scarce), Sheriff Sills called in the FBI, whose Behavioral Analysis Unit provided a profile.  Sheriff Sills described it as follows:

“The bottom line of the profile that was worked up was that it was a male subject who probably liked guns and knives and things like that. Well, guess what? That’s everybody in Georgia pretty much, certainly in middle Georgia. It’s not that I don’t appreciate the fact that the BAU looked at this case and gave us some good questions to ask when we formulated questions to ask people. But the profile just fits so many people.”  

The “guns and knives” angle is a useful piece of the puzzle.  But since we know that Mr. Dermond’s head was severed with a precise cut, that conclusion might have been more or less apparent just based on common sense.  We need many more pieces of the puzzle.  To find them and pull them together, I recommend a process known as triangulation:

  • Triangulation of data
  • Triangulation of methods
  • Triangulation of investigators

Simply put, triangulation involves combining, comparing, and contrasting different approaches to problem-solving.  This could involve having different experts involved in the investigation.  Sheriff Sills has already taken a step in this direction by involving the FBI.  It could include having experts outside law enforcement consider the evidence and apply their skills and knowledge to the case (much as I am doing now).  It could involve running down new leads – not leads that have been overlooked, but rather leads that have never even come up as possibilities (such as the ones I will offer below).

My analysis is based on publicly available information taken from the news.  Since I have not seen the case file, I have a limited grasp of the investigation.  Working within these constraints, I understand the following to be true: 

  • Sheriff Sills and the FBI believe there were at least 2 killers.  I agree. 
  • The killers dumped Mrs. Dermond’s body in the lake 6 miles from her house.  They probably did so as they made their getaway.   The Dermonds had no boat, so the killers must have arrived by boat (i.e., no vehicle)

 Now, with those two points in mind, and based on the available facts of the case, these are my observations and suggestions:

  • I concur with the FBI’s proposition that the killers are gun and knife enthusiasts, but I would further venture that the killers are hunters and, more specifically, deer hunters.  The clean cut to Mr. Dermond’s neck, combined with the fact that the killers came prepared to commit such butchery, suggests experience skinning and/or processing large game.  In central Georgia, that first and foremost means deer.  Accordingly, if I were investigating this case, I would cross-reference hunting licenses in Putnam and adjacent counties with individuals with criminal records, starting with felony convictions.  Which ones knew the Dermonds or performed work in that gated community?
  • Similarly, boat registrations and fishing licenses in Putnam and surrounding counties should be cross-referenced with persons having criminal records, focusing first on felonies.  Same question:  Which ones knew the victims or worked in that community?
  • I estimate the killers (or at least the dominant one) to be in the 30-45 age group, give or take a couple of years.  Male, of course.  I would expect at least one to have felony convictions.  A planned crime of this magnitude (and I believe it’s obvious that this was a planned crime and not a crime of opportunity) probably would not be a first offense. 
  • As would be obvious to Sheriff Sills, the criminals were familiar with Lake Oconee and surrounding area.  They are probably locals, or were at the time of the murders.  However, the lake attracts visitors from far and wide, so many outsiders are also familiar with the area.  Still, outsiders would be unlikely to know the Dermonds or to have any reason to commit such pointless violence against them.
  • Sheriff Sills believes Mr. Dermond’s head was removed to prevent ballistics testing of the bullet.  He may be right.  However, I would not rule out the possibility that the killer took the head as a trophy.  The brutality of this crime, the time that the killers spent decapitating Mr. Dermond, chaining concrete blocks to Mrs. Dermond, and transporting her 6 miles across the lake suggests an element of sadistic delight.  These activities are all beyond what was efficient for the killers.  They were enjoying this.  Mr. Dermond’s head could turn up as evidence once the right suspects are identified. 
  • As a further avenue of triangulation, I would recommend “shaking the bushes.”  Until the case is solved, I suggest that every encounter between sheriff’s office personnel and the public should include passing out a flyer with details about the case, photos of the Dermonds and their home, and a dedicated tip line.  If a reward can be offered, so much the better.  Every traffic stop, every witness interview, every arrest, every booking into county jail, etc. should include a flyer and request for any useful information.  From time to time – and especially on the anniversary of the murders – law enforcement agencies in surrounding counties should also be asked to pass out flyers and solicit information from people they come in contact with.
  • Ideally, a task force would be created to receive, review, analyze, and organize the information coming in via the triangulation process.  Otherwise the tips and leads would be scattered, unorganized, and randomly reviewed. 

Perhaps these insights and suggestions will be helpful to law enforcement.  Solving this murder mystery may require generating new tips and leads via triangulation rather than passively waiting for new information to come in.