Criminal Investigative Analysis in Sex-Related Homicide
The Application of Modus Operandi and Signature
By Vernon J. Geberth, M.S., M.P.S.
Homicide and Forensic Consultant
©2015 Vernon J. Geberth,
Practical Homicide Investigation
Originally published by Law & Order Magazine, Vol. 63 No. 6 June, 2015 pp
28-30
Under
the title, "Criminal Investigative ANALYSIS IN SEX-RELATED HOMICIDE
This PHI version of the Article has been expanded for Research and Clarity.
As a homicide investigator you should
focus on the similarities of cases as you develop an investigative
hypothesis. If you have a second victim killed in a similar
fashion with an M.O. and Signature that is
consistent with the other case than you must think of the
possibility of a serial killer.
Introduction
Criminal
investigative analysis, heretofore known as criminal profiling, is a systematic
methodology using clues left at a crime scene to gain insight about
the crime and the offender.
It is a process of combining knowledge of behavioral sciences
with the facts of the investigation.
Homicide
detectives follow logical steps during the investigation. They examine the
crime scene. They gather evidence and information from various sources. They
attempt to reconstruct the incident using the components of the crime including
forensic evidence and any physical and/or psychological attributes of the
offender to develop a theory about the incident. [1]
Investigators
then assess this data to see whether or not their theory is consistent with the
facts of the case and whether or not they can determine and interpret any
significant criminal behavior that will assist them in ascertaining the
identity of the offender. The investigators brainstorm the case during the
investigative critique. They use their intuition, follow hunches, and make
educated guesses based upon their extensive personal experience in homicide
investigation. In fact, an effective homicide
detective is usually someone who has taken his experience and has enhanced it
with knowledge, flexibility, and common sense.
The
process starts with some basic investigative questions as one examines the
facts and circumstances of the case. What took place? “Why did it occur? And
“Who could have done it”
The
investigator then attempts to ascertain the “Modus Operandi” utilized in the
offense and the “Signature” of the offender.
An
effective Criminal Investigative Analysis is synopsized as follows:
The Criminal
Investigative Analysis
u Analyzes the Initial Crime Scene
Investigation.
v Evaluates the Victimology.
w Evaluates the Physical and Trace
evidence.
x Reviews Wound Patterns.
y Evaluates the Toxicological
Examination Results.
z Evaluates the Geographical
Profile Information.
(including
demographics and crime patterns)
{ Analyzes
the Witness accounts.
| Performs a Personality Assessment
of any Potential Suspects.
Determining
Motivation
An extremely
important aspect of homicide investigation is the determination of the motive for the killing. In the sex-related homicide, there
are a number of possibilities to consider. Sex-related homicides include
rape–murders, serial murders, killings involving anal and oral sodomy and other
acts of sexual perversion, and interpersonal violence scenarios.
No one acts
without motivation. The motivations may
sometimes be revealed in the presentation of the body in the crime. The
investigative challenge is to discover this perverse or seemingly irrational
logic and then apply this information to the case.
A careful
search should always be conducted at the crime scene and within the surrounding
area for evidence of sexual activity. This includes the presence of sexual
assault activity as well as substitute and paraphilic behaviors. This evidence
may be seminal fluid in the vagina, mouth, nasal area, or rectum. Semen and
other evidence may be discovered outside the body or upon the clothing.
Pornographic books, videos, magazines, and/or photographs may be found at the
crime scene. The photographs may depict the victim involved in sexual activity.
Writings or messages may be left by the offender at the crime scene and/or upon
the body of the deceased. In any event, these factors are important in
determining the type of sexual activity that may have taken place.
Human
behavior, although unpredictable, is often repetitive. Research has indicated
that certain actions engaged in at the homicide crime scene by certain types of
personalities will be repeated in other homicide investigations. The homicide
detective who has enhanced his experience with a comprehension of the
psychodynamics of human behavior will be able to develop a base of knowledge
that can be applied to the review of similar cases.[2]
The reason
and motivation for the crime are an extremely important consideration in
establishing the investigative direction. Was the murder the result of a
lover’s quarrel?
Is the case
attributed to interpersonal violence? Does it appear the victim was killed
during a rape or sodomy attempt? Is the killing sexually oriented? Is there a
psychotic motive, which sometimes appears to be motiveless or bizarre? Is the
homicide the work of a sexual psychopath, with sadistic or impulsive
implications? Was the body sexually posed? What does this suggest? Each of
these scenarios suggests a specific course of action.
However, in
sex-related homicide investigations, the motivation behind the killing may not
be immediately ascertained. Even when you do believe that you have determined
the motive, my experience suggests exercising caution.
Determining
Motivation in Cases Involving Sexual Posing
Crime scene staging
and sexual posing and/or positioning of a body in a crime scene are recognized
homicide investigation phenomena and may provide the reason for such the
murder. presentation. Was the staging done to satisfy
some psychological need? Was the staging a result of anger or retaliation? Was
the staging done to evade detection?
How frequent these motivations are seen in staged or other homicides, or
how often staging actually occurs, are not typically recorded in justice system
data. The author conducted a survey on this phenomenon in a journal article
entitled; Crime Scene Staging: An
Exploratory Study of The Frequency and Characteristics of Sexual Posing in
Homicides[3]
The author had access to 185 cases of sexual posing in his dataset of
44,541 homicides. These 185 cases represented slightly less than 1% of all of
the homicides. Examination of these
cases revealed the offender’s motivation could be sorted into Three Categories.
Fantasy
Driven Behavior
This was the most common motivation. The posing was done to satisfy a
perverse sexual fantasy. Sexual Sadists
rely heavily on Fantasy and Ritual to obtain sexual satisfaction. The sexual manipulation of the victim’s body
including Posing, propping, sexual mutilation, defeminization
and evisceration are examples of fantasy driven behavior.
Anger/Retaliation
This is the second most common motivation in sexual manipulation of the
body. The offender used sex as a weapon to punish and degrade the woman. The posing of the body was done to further
degrade the victim out of anger or revenge.
Staging The Scene
This was the third motivation for sexual posing of the body. The offender
consciously attempted to mislead and thwart the police investigation by making
the murder appear to be sexual when in reality the murder was based on
interpersonal violence.
The
Identification of the Victim
The
identification of the victim is a crucial consideration in determining
motivation. An intensive investigation into the victim’s background, lifestyle,
and associations many times will reveal a possible motive. An examination of
any relationships, acquaintances, and risk factors may provide a clue to the “Who could have
done it?” scenario. For
example, “With whom does the victim
live?” “Who was
with the victim last?” “Does it
appear that the victim knew his or her assailant?” “What is the victim’s
current social status?” “Why was this particular victim selected”? “Does the crime appear to be a
“stranger-homicide?” “Was the deceased in a high-risk
occupation (call girl or prostitute)?”
Was the victim a runaway or?” “Was the victim a late-hours worker, e.g.,
waitress or service worker, who had to travel alone at night?” “What method of
transportation did the victim utilize”? “What route did the victim travel?”
“Were there any recent sexual incidents in the area, such as voyeurism (Peeping
Tom cases) or fetish burglaries? Are there any rape or sexual assault
patterns?”
One of the
most significant factors to consider in death investigation is victimology. In
sex-related events, victimology becomes paramount in the assessment and
analysis of “Who was the victim and what was going on in his
or her life at the time of the event?”[4]
The Crime Scene Assessment
At every crime scene the offender inadvertently leaves
messages or clues as to his or her identity, indicating the motivation and/or
drive for the crime. Crime scene
assessment focuses on the connection
among the major elements in a homicide investigation. Examples of the
major elements would be the location, the victim, the offender, crime scene
forensics and autopsy protocols.
The location where an offense took place and the
body disposal site can provide insight into the nature and background of an
offender. Research indicates that the distance
between the murder site and the disposal site is usually short.
Significant
scenes and routes to the scene to consider
● Last seen alive
● Initial contact scene
● Attack scene
● Murder site
● Body disposal site
A victim whose body was sexually mutilated dumped at
an outdoor location with all identification removed is highly suggestive of an
organized offender who engaged in these activities at one location and had
access to a vehicle in order to separate the event from his comfort zone. While a victim sexually assaulted and posed
in her residence might suggest an offender who resides in the area and may have
had some previous interaction with the victim. The evaluation of the wound
structures of a nude or semi-nude male victim who was found multiply stabbed in
the back and neck might suggest a sex crime where the offender who was
homosexually oriented.
Significant
Components to consider
●
Location of
offense
●
Method of
entry
●
Protection
of identity
●
Weapons used
●
Evidence of
Ritualistic Behavior
Crime scene forensics goes beyond the recovery of
physical evidence. The other
consideration is the significance of what the offender did in the scene, what
was done to the victim.
Significant
Components to consider
● Physical
Materials
● Victim incapacitation
● Sexual evidence
● Offender Forensically aware?
● Was the offender injured?
● Are there any missing items?
● Blood distribution
● Linking evidence
Modus Operandi and Signature
In
addition to victimology and presentation of the victim in the crime scene the
investigator must understand the significance of M.O. and Signature especially
in sex-related incidents.
Modus
Operandi is a learned
behavior that tends to change as offenders gain experience and/or build
confidence in their crimes. Some reasons
for a change in an offender M.O. could be attributed to experience, maturity,
education, incarceration/jail time, criminal versatility, and/or technology.
Some examples of modus operandi are an offender who brings a weapon, uses
a con, the times of crime, The days of the week, intelligence gathering
(Stalking), methods of control of victim, use of the victim’s vehicle, and the
location of crime scenes ((Inside or Outside).
Many serial offenders target prostitutes and their M.O. is simply to pose
as a “John” in order to get their victims away from an area and into a comfort
zone where they can act out their sexual fantasies. Richard Cottingham,
who was a serial killer operating in both New York City Bergen County, New
Jersey targeted prostitutes. In some
cases he would pick-up women in a New York City bar and slips a date-rape drug
into their drinks. He would then take them to a New Jersey hotel where he would
sexually assault and torture them. In some cases he left them nude and battered
with burns on their breasts. In other incidents if he felt they could identify
him he would kill them and leave their bodies in hotels in New York City and
New Jersey. He was a classic “Signature
Killer” and all of crimes were linked through his signature behavior.
Other sexual offenders establish a casual
relationship with a prospective victim that eventually allows them access to a
victim’s home. Once the offender was in the victim’s residence he would
sexually attack and kill them to prevent identification.
I consulted on one particular case where the offender had started out as
a “Cat Burglar” who entered victim’s homes in the middle of the night to steal
their valuables. On one particular
occasion he encountered a young women living alone. In a classic example of an
opportunistic crime, he sexually attacked and raped her. He then began to stalk and target women who
lived alone. The burglary and thefts became secondary to his primary intention,
which was to rape and sodomize his victims.
He was caught in one young woman’s home with his rape kit before he
could assault her. He was charged with
Burglary and Attempted Rape. He pled guilty to the Burglary and was
paroled. Within two weeks of his parole
he became a serial killer. He raped and sodomized four women during his home
invasions to satisfy his lust and then killed them to prevent them from
identifying him or ever being able to testify against him in court. . He was also classic “Signature Killer” and
all of crimes were linked by his specific type of binding the sexual activity,
his DNA and his modus operandi.
The Signature
Aspect of a violent
sexual offender is a unique and integral part of the offender’s behavior, which
refers to the psychodynamics of the event. The psychodynamics are the mental
and emotional processes underlying human behavior and its motivations.
The “Signature” aspect is the end result of a number of biological,
psychological and psychosocial factors that have combined to influence how an
individual seeks sexual satisfaction or is able to sexually perform. The
nucleus of the “Signature” element begins at an early age and is reinforced
through repetitive fantasy, masturbatory activity and situational “acting-out”
of these themes in various non-criminal scenarios.
Clinically
speaking, there is a behavioral distinctiveness in human sexuality. This unique
aspect of our arousal and response system accounts for why individuals differ
in their sexual behaviors. In my textbook, Sex-Related Homicide and Death
Investigation: Practical and Clinical Perspectives Second Edition[5] I devote an entire chapter
on the investigative significance of fantasy in sex-related incidents. Sexual fantasies play a major role in
everyone’s sexual behavior. It is the drive factor for sexual expression. The sexual offender and other individuals,
who are aroused with thoughts and fantasies of sexual aggression, reinforce
their beliefs through repetition illustrated by the use of sadistic pornography
and fantasy drawings. These serve as a
form stimulus and excitement, a rehearsal before actually committing the
offense or a mental re-creation of an actual event and represent the
“Signature” component.
Fantasies may
be used to organize a collection of deviant thinking into a criminal thought
pattern referred to as Premeditation.
As a person fantasizes over
time he feels the need to express these sexually violent Fantasies. Fantasy
Drawings and Writings and Journals are excellent examples of premeditation and
investigative evidence
Many Sexual Criminals are not just satisfied with the murder and have a
compulsion to express themselves. Unlike M.O. the Core
Signature is constant. However, over time the Signature Component
evolves. Some examples are overkill, mutilation, sexually posing the body, engaging
in post mortem activities. The victim is treated as a prop to be used to
fulfill their violent sexual fantasies as they progress from victim to victim
leaving their imprint at the scenes.
Dennis Rader, “The BTK Killer” would stalk his victims prior to the
murders to ascertain when they would be alone. His M.O. was to cut the
telephone wires at the victim’s home before entering. He broke into some homes and waited for the
victims to return. In one case he told his victims that he was on the run and needed
cash. He told them he would only tie them up so he could make his getaway. In
another case he pretended to be a student at Wichita State University and
carried books to blend into the neighborhood. He also purported to be a
detective and carried a briefcase to gain access to another victim’s home. Rader also pretended to be an ADT inspector
and a Southwest Bell telephone repairman. Although he used several different
M.O.’s his “Signature” remained constant. In each of the cases he would bind,
torture and kill his victims in a unique and distinctive manner with his
bindings. He strangled his victims to
death both manually and with ligature. In one case he strangled the young woman
unconscious and then brought her back and told her he was “BTK” as tightened
the belt around to kill her. He would then communicate with authorities and
taunt them with fantasy drawings and communications that he personalized with
his BTK symbol.
He wrote, “How many do I have to kill
before I get a name in the paper or some national attention…Yes the M.O. is
different in each, but look a pattern is developing…The victims are tie up
(sic) – most have been women-phone cut bring some bondage material-sadist
tendencies..”[6]
Rader kept all of the color Polaroid™ photos of his victims along with
his fantasy drawings and his original communications to authorities. He also
kept “trophies” of his conquests in the form of jewelry and personal items
taken from his victims so he could fantasize and re-live the murders in a
secret location that he referenced his “Mother Lode.” Dennis Rader’s
activities are an excellent example of the “Signature” aspect of the violent
sexual predator.
Offenders who engage in sexual activities do leave unique signatures,
which allow law enforcement to link their crimes and similar events. Although
the rituals may not be exactly the same or identical in nature the behavior of
the offender with his victim and the sexual theme will be consistent. The investigative question is, “What did
the offender do that went beyond that necessary to commit the crime?”
Conclusion
As a homicide investigator you should focus on the similarities of cases
as you develop an investigative hypothesis. If you have a second victim killed
in a similar fashion with an M.O. and Signature that is consistent with
the other case than you must think of the possibility of a serial killer.
Summation of
Modus Operandi versus Signature
The
Modus Operandi (M.O.) is the How?
What did the offender do to
accomplish the Act.
What did he do to ensure the
Success of the crime.
What did he do to protect his
identity and escape.
M.O. is a thought-driven
process based on past successes.
The Signature
is the Why
What did the offender do to the victim in the crime?
What
was the “Theme” of the event?
Signature
is a Fantasy-driven process
These
rituals are incorporated into the criminal act.
What
were the behavioral aspects to the event?
Bibliography
Geberth,
V.J. Practical Homicide Investigation:
Tactics, Procedures and Forensic Techniques 5th Edition CRC
Press, LLC Boca Raton, FL, pp.595-597 and 1013-1016,
2015
Geberth,
V.J. Practical Homicide Investigation: Tactics, Procedures and Forensic
Techniques 4th Edition CRC Press,
LLC Boca Raton, FL, p.773, 2006.
Geberth, V.J. Crime
Scene Staging: An Exploratory Study of the Frequency and Characteristics of
Sexual
Posing in Homicides.
Investigative Sciences Journal Vol2, Number 2 July, 2010.
Geberth,
V.J. Sex-Related Homicide and Death Investigation: Practical and Clinical Perspectives Second
Edition,
CRC Press, LLC Boca Raton, Florida 2010, page, 606.
Biography
Vernon J. Geberth, M.S., M.P.S. who holds dual Master's Degrees is the author
of Practical Homicide Investigation: Tactics, Procedures, and Forensic
Techniques 5th Ed. CRC Press, LLC 2015. He retired from the NYPD as The
Commanding Officer of The Bronx Homicide Task Force. These copyrighted
materials have been excerpted with Geberth's permission. He can be reached at www.practicalhomicide.com