Chapter 30 CRC Press: Forensic Science, James and Nordby, 2nd Edition 1# Forensic Science An Introduction to Scientific and Investigative Techniques Stuart H. James and Jon J. Nordby

2Chapter 30 CRC Press: Forensic Science, James and Nordby, 2nd Edition Chapter 30 Serial Offenders: Linking Cases by Modus Operandi and Signature Chapter Author: Robert D. Keppel Presentation created by Greg Galardi, Peru, Nebraska Presentation created by Greg Galardi, Peru, Nebraska

3Chapter 30 CRC Press: Forensic Science, James and Nordby, 2nd Edition Introduction to Crime Scene Assessment Outcomes possible from crime scene assessment (Keppel and Walter, 1999) include: Outcomes possible from crime scene assessment (Keppel and Walter, 1999) include: Determining the physical, behavioral, and demographic characteristics of the unknown offender Determining the physical, behavioral, and demographic characteristics of the unknown offender Developing post-offense behavior of the offender and strategies for apprehensions Developing post-offense behavior of the offender and strategies for apprehensions

4Chapter 30 CRC Press: Forensic Science, James and Nordby, 2nd Edition Introduction to Crime Scene Assessment Developing interviewing strategies once the offender is apprehended Developing interviewing strategies once the offender is apprehended Determining the signature of the offender Determining the signature of the offender Determining where the evidence may be located Determining where the evidence may be located

5Chapter 30 CRC Press: Forensic Science, James and Nordby, 2nd Edition Introduction to Crime Scene Assessment Information used for analysis may come from: Information used for analysis may come from: Police officer reports Police officer reports Statements Statements Crime laboratory results Crime laboratory results Photographs Photographs Videotapes of crime scenes Videotapes of crime scenes Autopsy reports Autopsy reports

6Chapter 30 CRC Press: Forensic Science, James and Nordby, 2nd Edition Historical Perspective MO- modus operandi or method of operation MO- modus operandi or method of operation Modus Operandi first appeared in literature in 1654 Modus Operandi first appeared in literature in 1654 Chief Constable Major L.W. Atcherly of England used ten categories related to an offender’s modus operandi in 1879 Chief Constable Major L.W. Atcherly of England used ten categories related to an offender’s modus operandi in 1879

7Chapter 30 CRC Press: Forensic Science, James and Nordby, 2nd Edition Atcherly’s 10 Categories Classword Classword Entry Entry Means Means Object Object Time Time Style Style Tale Tale Pals Pals Transport Transport Trademark Trademark

8Chapter 30 CRC Press: Forensic Science, James and Nordby, 2nd Edition Trademark Atcherly’s trademark was the precursor of what would have been known as the signature today Atcherly’s trademark was the precursor of what would have been known as the signature today Trademark, according to Atcherly, was whether the criminal committed any unusual act in connection with the crime- such as changing clothes, poisoning the dog, leaving a note Trademark, according to Atcherly, was whether the criminal committed any unusual act in connection with the crime- such as changing clothes, poisoning the dog, leaving a note

9Chapter 30 CRC Press: Forensic Science, James and Nordby, 2nd Edition What is a Killer’s Signature Also referred to as a killer’s psychological calling card Also referred to as a killer’s psychological calling card Homicide detectives are trained to look for unusual characteristics: victim left in a certain position, beaten or raped with a certain instrument Homicide detectives are trained to look for unusual characteristics: victim left in a certain position, beaten or raped with a certain instrument Subsequent killings of same type alert detectives to possible serial qualities Subsequent killings of same type alert detectives to possible serial qualities

10Chapter 30 CRC Press: Forensic Science, James and Nordby, 2nd Edition Differentiating MO and Signature MO is simply the way a particular criminal operates: MO is simply the way a particular criminal operates: Using a glass cutter to break into building Using a glass cutter to break into building Using a drill to open door locks Using a drill to open door locks Way entry was gained Way entry was gained

11Chapter 30 CRC Press: Forensic Science, James and Nordby, 2nd Edition Differentiating Modus operandi (MO) and Signature MO accounts for type of crime and property attacked, including the person, time and place of crime, tool or implements used, way of entry, how victim was caught, or how suspect represented himself to victim MO accounts for type of crime and property attacked, including the person, time and place of crime, tool or implements used, way of entry, how victim was caught, or how suspect represented himself to victim

12Chapter 30 CRC Press: Forensic Science, James and Nordby, 2nd Edition Signature Versus Modus Operandi FBI Behavioral Science Units and representatives, such as John Douglas, advise MO of killer is only those actions necessary to commit the murder FBI Behavioral Science Units and representatives, such as John Douglas, advise MO of killer is only those actions necessary to commit the murder

13Chapter 30 CRC Press: Forensic Science, James and Nordby, 2nd Edition Signature Versus Modus Operandi Signature is the killer’s compulsion to express themselves Signature is the killer’s compulsion to express themselves Imprint left at scene he feels psychologically compelled to satisfy himself sexually Imprint left at scene he feels psychologically compelled to satisfy himself sexually

14Chapter 30 CRC Press: Forensic Science, James and Nordby, 2nd Edition Signature Versus Modus Operandi FBI defends the signature aspect of a killer, saying that the elements of personal expression will only develop more fully over time FBI defends the signature aspect of a killer, saying that the elements of personal expression will only develop more fully over time According to Douglas, person’s violent fantasies progress in nature over time, and develops a need to develop those fantasies According to Douglas, person’s violent fantasies progress in nature over time, and develops a need to develop those fantasies

15Chapter 30 CRC Press: Forensic Science, James and Nordby, 2nd Edition Signature Versus Modus Operandi According to Gerberth (1996), it is simply not enough to consummate the murder, the killer must act out fantasies in some manner. According to Gerberth (1996), it is simply not enough to consummate the murder, the killer must act out fantasies in some manner. The acting out is the signature of the killer The acting out is the signature of the killer

16Chapter 30 CRC Press: Forensic Science, James and Nordby, 2nd Edition Signature Versus Modus Operandi Detectives who investigate a series of murder scenes look for the same type of extraordinary violence and a set of bizarre similarities Detectives who investigate a series of murder scenes look for the same type of extraordinary violence and a set of bizarre similarities A signatures constitutes a strong possibility the same person is committing the crime A signatures constitutes a strong possibility the same person is committing the crime

17Chapter 30 CRC Press: Forensic Science, James and Nordby, 2nd Edition Items a detective or investigator may look for at a crime scene: Items a detective or investigator may look for at a crime scene: How victim was placed, arrangement of crime scene, preoccupation with a certain aspect of the scene, mutilation, overkill, body carving, engaging in postmortem activity, making victim respond in a certain manner How victim was placed, arrangement of crime scene, preoccupation with a certain aspect of the scene, mutilation, overkill, body carving, engaging in postmortem activity, making victim respond in a certain manner Signature Versus Modus Operandi

18Chapter 30 CRC Press: Forensic Science, James and Nordby, 2nd Edition Signature Analysis Examples of clues to a serial killing in the Shoreline Murders Examples of clues to a serial killing in the Shoreline Murders Acts of binding occurring at consecutive murders Acts of binding occurring at consecutive murders Number of stabbing strokes necessary for killing Number of stabbing strokes necessary for killing Disposition of victim’s body- placement Disposition of victim’s body- placement Taking of souvenirs Taking of souvenirs Burning of bodies in certain areas Burning of bodies in certain areas

19Chapter 30 CRC Press: Forensic Science, James and Nordby, 2nd Edition Statistical Analysis Homicide Investigation and tracking System (HITS) in Washington State is a central repository for murder and sexual assault victims in state of Washington Homicide Investigation and tracking System (HITS) in Washington State is a central repository for murder and sexual assault victims in state of Washington System has 227 query capabilities System has 227 query capabilities Other states and federal agencies have similar systems Other states and federal agencies have similar systems

20Chapter 30 CRC Press: Forensic Science, James and Nordby, 2nd Edition Catching the Killer Necessary items to catch a killer: Necessary items to catch a killer: Thorough investigation of crime scene Thorough investigation of crime scene Cooperation with all agencies involved Cooperation with all agencies involved Review all evidence from witnesses Review all evidence from witnesses DNA analysis and laboratory analysis of evidence DNA analysis and laboratory analysis of evidence Coordinated efforts with prosecution Coordinated efforts with prosecution