By John E. Douglas, Ed.D. Special Agent, Chief of the Investigative Support Unit FBI Academy and Corinne Munn, Served as Honors Intern FBI Academy
Most crime scenes tell a story. And like most stories, crime scenes have characters, a plot, a beginning, a middle, and hopefully, a conclusion. However, in contrast to authors who lead their readers to a predetermined ending, the final disposition of a crime scene depends on the investigators assigned to the case. The investigators' abilities to analyze the crime scene and to determine the who, what, how, and why govern how the crime scene story unfolds.
To ensure a satisfactory ending, that is, the apprehension and prosecution of the violent crime offender, investigators must realize that the outcome depends on their insight into the dynamics of human behavior. Speech patterns, writing styles, verbal and nonverbal gestures, and other traits and patterns give shape to human behavior. These individual characteristics work in concert to cause each person to act, react, function, or perform in a unique and specific way. This individualistic behavior usually remains consistent, regardless of the activity being performed.
Since the commission of a violent crime involves all the dynamics of "normal" human behavior, learning to recognize crime scene manifestations of behavioral patterns enables investigators to discover much about the offender. It also provides a means by which investigators can distinguish between different offenders committing the same types of offense.
There are three possible manifestations of offender behavior at a crime scene--modus operandi, personation or signature, and staging. This article addresses each of these manifestations in order to demonstrate the importance of analyzing a crime scene in terms of human behavior.
In 1989, Nathaniel Code, Jr., a Shreveport, Louisiana, man, was convicted of murder. The jury determined that on three separate occasions between 1984 and 1987, Code murdered a total of eight people. The jury returned a guilty verdict, even though several disparities existed among the three crime scenes.
For example, the offender gagged the first victim with a piece of material obtained at the crime scene, but brought duct tape to use on the seven victims in the other two incidents. Also, the killer stabbed and slashed the first victim, whereas the victims of the other two crimes were also shot and showed signs of ligature strangulation. The victims ranged in age from 8 years to 74 years and included both sexes; however, all were black. And, the offender took money from one crime scene, but not the other two.
Considering the evidence found at the three crime scenes, could one man be linked to all of the murders? Wouldn't such differences in modus operandi (M.O.), which is the offender's actions while committing the crime, and victimology (characteristics of the victims) eliminate the connection to one offender?
When attempting to link cases, the M.O. has great significance. A critical step in crime scene analysis is the resulting correlation that connects cases due to similarities in M.O. But, what causes an offender to use a certain M.O.? What circumstances shape the M.O.? Is the M.O. static or dynamic?
Unfortunately, investigators make a serious error by placing too much significance on the M.O. when linking crimes. For example, a novice burglar shatters a locked basement window to gain access to a house. Fearing that the sound of a window breaking will attract attention, he rushes in his search for valuables. Later, during subsequent crimes, he brings tools to force open locks, which will minimize the noise. This allows him more time to commit the crimes and to obtain a more profitable haul.
As shown, the burglar refined his breaking-and-entering techniques to lower the risk of apprehension and to increase profits. This demonstrates that the M.O. is a learned behavior that is dynamic and malleable. Developed over time, the M.O. continuously evolves as offenders gain experience and confidence.
Incarceration usually impacts on the future M.O.s of offenders, especially career criminals. Offenders refine their M.O.s as they learn from the mistakes that lead to their arrests.
The victim's response also significantly influences the evolution of the M.O. If a rapist has problems controlling a victim, he will modify the M.O. to accommodate resistance. He may use duct tape, other ligatures, or a weapon on the victim. Or, he may blitz the victim and immediately incapacitate her. If such measures are ineffective, he may resort to greater violence or he may kill the victim. Thus, offenders continually reshape their M.O. to meet the demands of the crime.
In the case of Nathanial Code, M.O. and victimology alone would have failed to link him to each of the eight murders. But Code left more than gags, duct tape, and bodies with gunshot wounds and slashed throats at the crime scenes; he left his "calling card." Investigators found this "calling card" or signature aspect at every crime scene, and thus, were able to link Code to the offenses.
THE SIGNATURE ASPECT
The violent, repetitive offender often exhibits another element of criminal behavior during the crime--the signature aspect or "calling card." This criminal conduct is a unique and integral part of the offender's behavior and goes beyond the actions needed to commit the crime.
Fantasies of offenders often give birth to violent crime. As offenders brood and daydream, they develop a need to express these violent fantasies. When they are finally acted out, some aspect of each crime demonstrates a unique, personal expression or ritual based on these fantasies. However, committing the crime does not satisfy the needs of offenders, and this insufficiency compels them to go beyond the scope of the offense and perform a ritual. When offenders display rituals at the crime scene, they have left their individualized "calling card."
How do crime scenes manifest this "calling card" or signature aspect? Basically, crime scenes reveal peculiar characteristics or unusual offender input that occur while the crime is being committed.
For example, a rapist demonstrates his signature by engaging in acts of domination, manipulation, or control during the verbal, physical, or sexual phase of the assault. The use of exceptionally vulgar or abusive language, or preparing a script for the victim to repeat, represents a verbal signature. When the rapist prepares a script for a victim, he dictates a particular verbal response from her, such as "Tell me how much you enjoy sex with me," or "Tell me how good I am."
The use of excessive physical force shows another aspect of a subject's signature. One example of signature sexual behavior involves the offender who repeatedly engages in a specific order of sexual activity with different victims.
The signature aspect remains a constant and enduring part of each offender. And, unlike the M.O., it never changes. However, signature aspects may evolve, such as in the case of a lust murderer who performs greater postmortem mutilation as he progresses from crime to crime. Elements of the original ritual become more fully developed. In addition, the signature does not always show up at every crime scene because of unexpected contingencies, such as interruptions or an unexpected victim response.
The investigator may not always be able to identify signature aspects. Violent offenses often involve high-risk victims or decomposition of the body, which complicates recognizing the signature aspects of an offender.
MODUS OPERANDI OR SIGNATURE ASPECT?
The following scenarios are fictitious accounts. They are used to show the difference between a M.O. and a signature aspect.
A rapist enters a residence and takes a woman and her husband captive. The offender orders the husband to lie face down on the floor and then places a cup and saucer on his back. He tells the husband, "If I hear the cup move or hit the floor, your wife dies." The offender then takes the wife into the next room and rapes her.
In another situation, a rapist enters the house, orders the woman to phone her husband, and tells her to use some ploy to get him to come home. Once the husband arrives, the rapist ties him to a chair and forces him to watch the assault on his wife.
The rapist who used the cup and saucer developed an effective modus operandi to control the husband. However, the other rapist went beyond just committing the rape. He satisfied his fantasies fully by not only raping the wife but also by humiliating and dominating the husband. His personal needs compelled him to perform this signature aspect of the crime.
In Michigan, a bank robber makes the bank tellers undress during the robbery. In Texas, another bank robber also forces the tellers to undress, but he also makes them pose in sexually provocative positions as he takes photographs. Do both of these crimes demonstrate a signature aspect?
The Michigan robber used a very effective means to increase his escape time, i.e., causing the tellers to dress before they called the police. When interviewed, they offered vague, meager descriptions because their embarrassment prevented them from having eye contact with the robber. This offender developed a very clever M.O.
However, the Texas robber went beyond the required action to commit his crime successfully. He felt compelled to enact the ritual of requiring the tellers to pose so that he could snap photographs. He left his signature on the crime. The act of robbing the bank itself did not gratify his psychosexual needs.
When attempting to link cases, the M.O. plays an important role. However, as stated previously, the M.O. should not be the only criteria used to connect crimes, especially with repeat offenders who alter their M.O. through experience and learning. Usually, first offenses differ considerably from subsequent offenses. However, the signature aspect stays the same, whether it is the first offense or one committed 10 years later. The ritual may evolve, but the theme remains constant.
The signature aspect should receive greater consideration than victim similarities, although these should never be discounted when attempting to link cases to a serial offender. Physical similarities of victims are often not important, especially when linking crimes motivated by anger. The offender expresses anger through rituals, not by attacking a victim who possesses a particular characteristic or trait.
CASES LINKED BY OFFENDER SIGNATURE
Ronnie Shelton: Serial Rapist
Ronnie Shelton committed as many as 50 rapes. When convicted of 28 of them, he received a prison sentence in excess of 1,000 years.1 Both his verbal communication and sexual assaults manifested his signature.
Verbally, Shelton was exceptionally degrading and exceptionally vulgar. In addition, he would make such comments as "I have seen you with your boyfriend," "I've seen you around," or "You know who I am." Thoughts of Shelton lurking around their neighborhoods terrorized the victims.
However, it was the sexual assault itself that occupied the central position in Shelton's ritual. He would rape his victims vaginally, then withdraw and ejaculate on their stomachs or breasts. Shelton would also frequently masturbate over the victims or between their breasts or force them to masturbate him manually. Then, he would use their clothing to wipe off the ejaculation. He also forced many of his victims to have oral sex with him and then insisted that they swallow the ejaculation. The combination of these acts displayed Shelton's signature.
Shelton's M.O. consisted of entering the victim's dwelling through a window or patio entrance that faced a wooded area or bushes offering concealment. He wore a ski mask, stocking, or scarf. He convinced the victims that he was not there to rape but to rob them. However, when he had the victim under control, he would return to the rape mode. The victim would comply because she had seen his propensity for violence by his earlier actions, such as throwing her on the floor or holding a knife to her throat. In addition, Shelton would say to the victims, "Keep your eyes down," "Cover your eyes," or "Don't look at me and I won't kill you (hurt your kids)." Before he left, he would verbally intimidate them with such warnings as "Don't call the police or I'll come back and kill you." These characteristics served as Shelton's M.O., whereas his former actions were his signature that linked him to 28 sexual assaults.
Nathaniel Code: Serial Killer
Nathaniel Code, Jr., killed eight times on three separate occasions. The first homicide, a 25-year-old black female, occurred on August 8, 1984. Code stabbed her nine times in the chest and slashed her throat.
Approximately a year later, on July 19, 1985, Code killed four people--a 15-year-old girl, her mother, and two of their male friends. Code nearly severed the girl's head from her body. He asphyxiated the mother and draped her body over the side of the bath tub. Code then shot one of the males in the head, leaving him in a middle bedroom; the other male, who was found in the front bedroom, was shot twice and had his throat slit.
The last killing took place on August 5, 1987. The victims were Code's grandfather and his 8-year-old and 12-year-old nephews. The boys died of ligature strangulation. Code stabbed his grandfather five times in the chest and seven times in the back.
The changes in Code's M.O., exhibited from case to case, show how the M.O. is refined. For example, in the first murder, Code gagged the victim with material found at the scene; the next time, he brought duct tape.
Code also kept his victims under surveillance to obtain information on them, especially with the second killings. In that case, he brought a gun to the scene to dispose of the males, who posed the greatest threat to him. Since the last victims, an elderly man and two children, posed little threat to him, Code did not use a gun on them. All eight killings occurred in single family dwellings. In each dwelling, the air conditioners and/or televisions were on, which drowned out the noise as he entered through a door or window. Code quickly gained and maintained control of the victims by separating them in different rooms.
Nathaniel Code had a very distinctive "calling card," one aspect of which were the injuries inflicted on the victims. Code employed a very bloody method of attack and overkill. He could have simply murdered each victim with a single gunshot wound--a clean kill involving very little "mess." Instead, Code slaughtered his victims by slashing their throats with a sawing motion that resulted in deep wounds. Although brutal, the attack didn't satisfy his ritual; all victims sustained additional injuries, with the exception of the 15-year-old girl. One male victim suffered gunshot wounds to the chest, while another received multiple stab wounds to the chest. Code wounded nearly all the victims far beyond what was necessary to cause death (overkill).
The physical violence and bloody overkill satisfied Code's need for domination, control, and manipulation. He positioned each victim face down, which supports this theory. Code even forced the mother to witness her daughter's death as part of this ritual of control, which was formed from his rage. In fact, forensic tests found the daughter's blood on the mother's dress. If the victim's response threatened his sense of domination, Code reacted with anger and the excessive violence that led to overkill.
The last signature aspect of Code's crimes probably best illustrates his unique "calling card"--the ligatures. Code used both an unusual configuration and material. In all three cases, he bound the victims with electrical appliance or telephone cords acquired at the scene. Code could have brought rope or used his duct tape, but the use of these cords satisfied some personal need. Using a handcuff-style configuration, he looped the cord around each wrist and then the ankles, connecting them to the wrists by a lead going through the legs.
The dissimilarities of these cases involves the M.O., not the signature aspect. The use of a gun with threatening males present reveals an adaptive offender. At the time of the grandfather's homicide, additional financial stressors affected Code, evidenced by the theft of money from his grandfather's residence. These financial stressors influenced Code's M.O., not his "calling card."
Physical characteristics, age, and even sex do not enhance or diminish the ritual driven by rage. Code's ritual of anger required control and domination of his victims, so victimology was not as important. Code, like Ronnie Shelton, the serial rapist, selected victims he could control, manipulate, and on whom he could project his anger.
IMPORTANCE OF OFFENDER SIGNATURE
Understanding and recognizing the signature aspects is vital in the apprehension and prosecution of an offender, especially a serial offender. No one appreciates the importance of recognizing an offender's "calling card" more than David Vasquez.
In 1984, Vasquez pled guilty to the murder of a 34-year-old Arlington, Virginia, woman. The woman had been sexually assaulted and died of ligature strangulation. The killer left her lying face down with her hands tied behind her back. He used unique knots and excessive binding with the ligatures, and a lead came from the wrists to the neck over the left shoulder. The body was openly displayed so that discovery offered significant shock value.
The offender spent considerable time at the crime scene. He made extensive preparations to bind the victim, allowing him to control her easily. His needs dictated that he move her around the house, exerting total domination over her. It appeared that he even took her into the bathroom and made her brush her teeth. None of this behavior was necessary to perpetrate the crime; the offender felt compelled to act out this ritual.
Vasquez had a borderline I.Q. Believing this would make it difficult to prove his innocence, his lawyers convinced him that he would probably receive the death sentence if the case went to trial. Instead, Vasquez opted for life imprisonment by pleading guilty.
Three years later, in 1987, police discovered a 44-year-old woman lying nude and face down on her bed. A rope bound her wrists behind her back, and a ligature strand tightly encircled her neck with a slip knot at the back. It continued over her left shoulder, down her back, and then was wrapped three times around each wrist. Forensics revealed that she died of ligature strangulation, and that she had been sexually assaulted. The offender left the body exposed and openly displayed. He appeared to have spent a considerable amount of time at the crime scene. This homicide occurred 4 blocks from the 1984 murder.
David Vasquez had been imprisoned 3 years when the 1987 murder occurred. At the request of the Arlington, Virginia, Police Department, the National Center for the Analysis of Violent Crime (NCAVC) conducted an extensive analysis of these two murders, a series of sexual assaults, and several other killings that occurred between 1984 and 1987. Eventually, the NCAVC linked these offenses through analogous signature aspects of another local suspect. Physical evidence later corroborated this connection and determined that the "calling card" left at the 1984 homicide did not belong to David Vasquez. As a result of this finding, the Commonwealth of Virginia released Vasquez from prison and exonerated him of the crime.
When investigators approach a crime scene, they should look for behavioral "clues" left by the offender. This is when investigators attempt to find answers to several critical questions. How did the encounter between the offender and victim occur? Did the offender blitz (ambush) the victim, or did he use verbal means (the con) to capture her? Did the offender use ligatures to control the victim? What was the sequence of events? Was the victim sexually assaulted before or after death? When did the mutilation take place--before or after death? Did the offender place any item at the crime scene or remove something from the crime scene?
As investigators analyze crime scenes, facts may arise that baffle them. These details may contain peculiarities that serve no apparent purpose in the perpetration2 of the crime and obscure the underlying motive of the crime. This confusion may be the result of a crime scene behavior called staging. Staging occurs when someone purposely alters the crime scene prior to the arrival of the police.
Reasons for Staging
Principally, staging takes place for two reasons--to direct the investigation away from the most logical suspect or to protect the victim or victim's family. It is the offender who attempts to redirect the investigation. This offender does not just happen to come upon a victim, but is someone who almost always has some kind of association or relationship with the victim. This person, when in contact with law enforcement, will attempt to steer the investigation away from himself, usually by being overly cooperative or extremely distraught. Therefore, investigators should never eliminate a suspect who displays such distinctive behavior.
The second reason for staging, to protect the victim or the victim's family, occurs for the most part in rape-murder crimes or autoerotic fatalities. This type of staging is performed by the family member or person who finds the body. Since perpetrators of such crimes leave their victims in degrading positions, those who find the bodies attempt to restore some dignity to the victim. For example, a husband may redress or cover his wife's body, or in the case of an autoerotic fatality,3 a wife may cut the noose or the device suspending the body of her husband.
Basically, these people are trying to prevent future shock that may be brought about by the position, dress, or condition of the victim. In addition, they will often stage an autoerotic fatality to look like a suicide, perhaps even writing a suicide note. They may even go so far as to the make it appear to be a homicide.
For both types of crime scene investigations, rape-murders and autoerotic fatalities, investigators need to obtain an accurate description of the body's condition when found and to determine exactly what the person who found the body did to alter the crime scene. Scrutiny of forensic findings, crime scene dynamics, and victimology will probably reveal the true circumstances surrounding the deaths.
Finally, at some crime scenes, investigators must discern if the scene is truly disorganized or if the offender staged it to appear careless and haphazard. This determination not only helps to direct the analysis to the underlying motive but also helps to shape the offender profile. However, recognition of staging, especially with a shrewd offender, can be difficult. Investigators must examine all factors of the crime if they suspect it has been staged. This is when forensics, victimology, and minute crime scene details become critical to determine if staging occurred.
Offenders who stage crime scenes usually make mistakes because they arrange the scene to resemble what they believe it should look like. In so doing, offenders experience a great deal of stress and do not have the time to fit all the pieces together logically. As a result, inconsistencies in forensic findings and in the overall "big picture" of the crime scene will begin to appear. These inconsistencies can serve as the "red flags" of staging, which serve to prevent investigations from becoming misguided.
To ensure this doesn't happen, investigators should scrutinize all crime scene indicators individually, then view them in context with the total picture. Crime scene indicators include all evidence of offender activity, e.g., method of entry, offender-victim interaction, and body disposition.
When exploring these issues, investigators should consider several factors. For example, if burglary appears to be the motive, did the offender take inappropriate items from the crime scene? In one case submitted to the National Center for the Analysis of Violent Crime (NCAVC), a man returning home from work interrupted a burglary in progress. The startled burglars killed him as he attempted to flee. But, an inventory of the crime scene determined that the offenders did not steal anything, although it did appear that they started to disassemble a large stereo and TV unit.
Further examination of the crime scene revealed that they left smaller, and easily transported, items of far greater value (jewelry, coin collection, etc.). The police subsequently determined that the victim's wife paid the burglars to stage the crime and kill her husband. She, in fact, was having an affair with one of the suspects.
Another factor to consider is the point of entry. Did the point of entry make sense? For example, did the offender enter the house through a second-story window, even though there was an easier, less conspicuous entrance that could have been used? Why did the offender increase his chance of being seen by potential witnesses who might alert authorities?
Investigators should also consider whether the offender put himself at high risk by committing the crime during the daylight hours, in a populated area. If the crime scene is a place of residence, they should also evaluate any obvious signs of occupancy, such as lights on in the house, vehicles in the driveway, etc.
The following case scenario brings to light some "red flags" that investigators should look for at a crime scene.
One Saturday morning, in a small Northeastern city, an unknown intruder attacked a man and his wife. By placing a ladder against the house, the suspect made it appear that he had climbed to a second-story window, removed the screen, and entered the residence. All this occurred in a residential area during a time when neighbors were doing their weekend chores and errands.
The husband claimed that he heard a noise downstairs, so he went with a gun to investigate. A struggle with the intruder ensued, during which the husband was left unconscious by a blow to the head.
Presumably, the intruder then went upstairs and killed the wife by manual strangulation. He left the body with a nightgown pulled up around the victim's waist, implying that he sexually assaulted her. The couple's 5-year-old daughter remained unharmed, asleep in the next room.
While processing the crime scene, detectives noted that the ladder made no impression in the moist soil near the house, although it did when they tried to climb the ladder. Also, the intruder positioned the ladder with the rungs facing away from the house, and many of the rungs on the wooden ladder had rotted, making it impossible for it to support anyone weighing over 50 pounds.
In addition, the crime scene raised questions that could not be answered logically. Why didn't the offender choose to enter the residence through a first-story window to decrease the possibility of detection by both the occupants and neighbors? Why did the offender want to burglarize the residence on a Saturday morning when there was a good chance that he would be seen by neighbors? Why did the intruder choose a residence that was obviously occupied (several vehicles were in the driveway)?
Inside the residence, other inconsistencies became apparent. For example, if the intent was murder, the intruder did not seek his victim(s) immediately, but went downstairs first. He also did not come equipped to kill because, according to the one witness, the husband, he never displayed a weapon. Also, the person posing the most threat, the husband, received only minor injuries.
By analyzing the crime scene, which revealed excessive offender activity, it became apparent that there was no clear motive for the crime. Therefore, based on the numerous inconsistencies found at the crime scene, NCAVC criminal investigative analysts conclud-ed that the husband staged the homicide to make it appear to be the work of an intruder. He was eventually convicted of his wife's murder.
Forensic "Red Flags"
Forensic results that don't fit the crime should also cause investigators to consider staging. Personal assaults should raise suspicion, especially if material gain appears to be the initial motive. These assaults could include the use of a weapon of opportunity, manual or ligature strangulation, facial beating (depersonalization), and excessive trauma beyond that necessary to cause death (overkill). In other words, do the injuries fit the crime?
Sexual and domestic homicides usually demonstrate forensic findings of a close-range, personal assault. The victim, not money or property, is the primary focus of the offender. However, this type of offender will often attempt to stage a sexual or domestic homicide that appears to be motivated by personal gain. This does not imply that personal assaults never happen while a property crime is being committed, but usually these offenders prefer quick, clean kills that reduce the time spent at the scene.
Forensic red flags are also raised when there are discrepancies between witness/survivor accounts and forensics results. For example, in one case, an estranged wife found her husband in the tub with the water running. Initially, it appeared as if he slipped and struck his head on a bathroom fixture, which resulted in his death by drowning. However, toxicological reports from the autopsy showed a high level of valium in the victim's blood. Also, the autopsy revealed several concentrated areas of injury or impact points on the head, as if the victim struck his head more than once.
Subsequently, investigators learned that the wife had been with the victim on the evening of his death. She later confessed that she laced his dinner salad with valium, and when he passed out, she let three men into the house. These men had been hired by the wife to kill the victim and to make it look like an accident.
Often, investigators will find forensic discrepancies when an offender stages a rape-murder, that is, positioning the body to infer sexual assault. And if the offender has a close relationship with the victim, he will only partially remove the victim's clothing, never leaving her completely nude. However, despite the position of the body and the removal of some of the victim's clothes, an autopsy can confirm or deny whether any form of sexual assault took place, thereby determining if the crime scene was staged.
If investigators suspect a crime has been staged, they should look for signs of association between the offender and the victim. Or, as is frequently the case with domestic violence, the involvement of a third party, who is usually the one who discovers the victim. For example, in the case involving the husband who staged his wife's murder to make it look like the crime was committed by an intruder, the husband did not immediately check on his wife and daughter once he regained consciousness. Instead, he remained downstairs and called his brother, who went upstairs and discovered the victim. Offenders will often manipulate the discovery of victims by a neighbor or family member, or conveniently be elsewhere when the victim is discovered.
Violent crime scenes require investigators to be "diagnosticians." They must be able to analyze crime scenes for the messages they emit and understand the dynamics of human behavior displayed at crime scenes. Investigators must also be able to recognize the different manifestations of behavior, so they can ask the right questions to get valid answers.
By approaching each crime scene with an awareness of these factors, investigators can steadily improve their ability to read the true story of each violent crime scene. By doing so, they will be more knowledgeable and better equipped to apprehend the violent crime offender.
SA Douglas has qualified as an expert in criminal investigative analysis and has provided testimony in the area of signature crime analysis during the following court proceedings: State of Ohio v. Ronnie Shelton, State of Louisiana v. Nathaniel Code, and State of Delaware v. Steven B. Pennell.
P.E. Dietz, M.D. and R.R. Hazelwood, "Atypical Autoerotic Fatalities," Medicine and Law, 1, 1982, 301-319.
This Article Originally Appeared in the FBI Law Enforcement Bulletin, February 1992.