Differentiating forensic from clinical psychiatry

In clinical psychiatry, the goal is to improve the patient’s condition through a trusting relationship. If successful, the patient opens up and tells the psychiatrist what he needs to know to develop the proper treatment plan. The process is cooperative, and the psychiatrist doesn’t make moral or value judgments about the patient.

Forensic psychiatry, in distinct areas, is just the opposite. It’s adversarial, rather than cooperative. It’s judgmental in that the legal system is designed to make moral judgments concerning responsibility. The goal isn’t treating the individual but rather dissecting that person’s personality to reveal hidden motives. In short, the subject and the forensic psychiatrist often are at odds.

In the clinical arena, the patient has every reason to be truthful. After all, the patient and physician want the patient to get better. In the forensic setting, however, subjects have many reasons to lie or deceive, wanting to hide the truth about their actions and thoughts, especially if they happen to be guilty. Subjects also want their possible motivations for committing a crime to remain buried within themselves. They may fabricate or exaggerate symptoms to create an insanity defense. They’re likely to view the psychiatrist as an enemy rather than a friend and healthcare professional.

How the mind matters in forensics

Forensic psychiatrists can become involved in both criminal and civil matters. In the criminal arena, they may be brought to the case by the prosecution, the defense, or the judge. They’re often involved in homicides, robberies, kidnappings, and cases of assault, battery, and sexual misconduct. They may be asked to

• Assess the role of alcohol and drugs in a defendant’s conduct
• Determine sanity or competency to stand trial
• Assess a subject’s understanding of reality and responsibility
• Offer a judgment regarding the suspect’s state of mind at the time of the crime
• Offer investigators information for use in witness and suspect interrogations
• Create a psychological profile of the type of individual who likely committed the crime

In civil cases, the forensic psychiatrist may be asked to determine subjects’ competency to sign wills and contracts, manage personal affairs, vote, care for themselves or others, offer testimony, or stand trial. Spousal and child abuse also are common areas of involvement, and so are disputes involving child custody, sexual harassment, disability, or emotional suffering.

In cases of apparent suicide, the forensic psychiatrist may be asked to perform a psychological autopsy (see the later section, “Profiling the victim: Victimology”) to determine whether the victim likely took her own life and whether drugs and alcohol, financial problems, or social difficulties contributed to the death. Interviews with family, friends, and co-workers may reveal the victim’s behavior during the period before the tragedy and point the forensic psychiatrist in the right direction.

Getting started with a medical history and physical exam

When first examining a subject, the forensic psychiatrist determines whether the individual has any neurological or psychiatric problems that can alter his thinking and understanding. Medical problems, such as strokes, certain liver or kidney diseases, head trauma, and many medications can impact the assessment of the subject. For example, a stroke can alter your cognitive abilities so that you can’t form complete and coherent thoughts. It may damage areas of the brain that control speech, hearing, emotions, and any other brain function. Because these medical conditions can greatly affect the subject’s performance on the various psychiatric tests, they must be addressed before any psychological testing is undertaken.

Many prescription and illicit drugs alter brain function. Medications for seizure disorders, diabetes, heart disease, insomnia, and weight loss, in addition to essentially every known sedative and mood elevator, can affect psychiatric functional testing.

A review of the subject’s medical, work, and military records is undertaken, and if the subject is a suspect in a crime, police and witness reports, crime-scene photos, and autopsy reports (in cases where a death was involved) also are reviewed and considered. Blood testing and perhaps specialized brain testing such as an electroencephalogram (EEG), magnetic resonance imaging (MRI), or computed tomography (CT) brain scan are next. If these examinations are normal, the psychiatrist proceeds with the evaluation and testing of the subject.

Digging into the psyche

Options abound for testing a subject’s mental health, intellectual capacity, personality type, cognitive abilities, and mental competence. Each psychiatric professional chooses tests according to the particular situation and subject.

Tests fall into three categories:

• Personality inventories are designed to determine the subject’s basic personality type, which includes his attitudes, behaviors, thought processes, beliefs, emotional responses, and social abilities. These tests, which may reveal antisocial tendencies, obsessive-compulsive disorders, and other disorders, are highly standardized and reliable.

  Common personality inventories include the Minnesota Multiphasic Personality Inventory (MMPI), the Millon Clinical Multiaxial Inventory (MCMI), and the California Psychological Inventory (CPI). Chances are you’ve taken one or more of these tests at some point during your schooling.

• Projective testing is designed to evaluate the person’s personality and thought processes. These tests are less standardized and more subjective than personality inventories. The examiner uses them to gain insight into how the subject thinks and how he views himself, others, and the world in general. They also often uncover any obsessions and fantasies that drive the subject’s actions. The following tests are commonly used:
  • The Rorschach test is the famous inkblot exam. The subject views a series of abstract inkblots and is asked to describe what he sees. How the subject describes the images can reveal something about his personality, thought processes, and connections with reality. The test can also offer clues about the subject’s inner fantasies.
  • Projective drawing is similar to the Rorschach test, except the subject produces the drawings, which then are analyzed. The person may be asked to draw a house, a car, a tree, a member of the opposite sex, or a frightening scene or situation. The drawings can reveal the subject’s inner thought processes and fantasies. For example, if the subject draws images of a house that’s on fire, a woman who’s been stabbed, or a leafless tree with broken branches, such drawings may provide a look into the subject’s inner world.
  • In the Thematic Apperception Test (TAT), the subject is shown pictures of common situations and asked to make up stories to go with the images. Again, the subject’s inner thoughts and fantasies may be revealed. For example, when shown a photo of a man and a woman talking, the subject may relate a tale of how the two are planning their wedding, arguing about money, or saying negative things about the subject. Each story indicates a different psychiatric state.
• Intellectual and cognitive testing is designed to assess the subject’s intelligence, mental competency, thought processes, and ability to understand his own behavior. This information is critical in determining the subject’s level of responsibility and competency to stand trial. The most common intelligence test is the Wechsler Adult Intelligence Scale (WAIS), which assesses the subject’s intelligence quotient (IQ).

Asking the right questions

After these tests are completed and evaluated, the forensic psychiatrist interviews the subject, probing deeper into any areas of concern uncovered by the testing process.

In general, the psychiatrist first tries to get the subject to relax and to gain his confidence so the subject will speak freely. Simple, nonconfrontational questions about the subject’s childhood, family, and social interactions usually do the trick. If the subject has suffered any illnesses or injuries that may impact his psychiatric state or mental health, these are explored.

The questions gradually become more probing as the psychiatrist works to determine the subject’s attitudes toward past and current events in his life. Ultimately, the questions focus on the events that brought the subject to the psychiatrist in the first place.

The psychiatrist is more interested in the suspect’s motivation than in the actual events. For example, if the subject has assaulted someone, the questions will be designed to determine why he did it and how he felt about it. If the subject is ashamed and apologetic and realizes that he was wrong, that will say something very different about him than if he feels anger, resentment, justification, and entitlement.

Employing dubious techniques

Two interview techniques, hypnosis and the use of drugs during the interview, are controversial but nonetheless show up in interrogations real and fictional.

Hypnosis, the induction of a trance-like, highly relaxed state, is used to help suspects and witnesses recall certain events and details. One problem: Faking hypnosis is not that difficult, so any information obtained by this technique requires corroboration. In addition, people who are under the influence of hypnosis often are highly susceptible to suggestion, such that merely asking them questions can alter their memories of certain events. It’s possible for these new memories to become part of their real memory, thus jeopardizing any future interviews or court testimony they may provide. Not all courts allow testimony from previously hypnotized witnesses.

Although there’s no such thing as a truth serum, certain drugs nevertheless can lower the subject’s inhibitions and defenses. Sodium pentothal is the classic so-called truth serum. A short-acting barbiturate that causes drowsiness and euphoria, it can make the recipient quite chatty. As with hypnosis, however, any information gleaned in this fashion is suspect and is likely to face a challenge in court.

Though in real life it is very unlikely that any evidence gleaned by either of these techniques would be allowed in the courtroom, both are often found in fiction.

Recognizing lying perps

Distortion, exaggeration, and deception are the bane of the forensic psychiatrist’s existence. Suspects are extremely likely to lie, regardless of whether they view forensic psychiatrists as enemies or possible allies in deception. After all, if suspects can convince forensic psychiatrists that they’re telling the truth, that they remember nothing about the crime, or that they’re insane, they ultimately end up with an ally in the courtroom.

Say, for example, that a suspect is indeed guilty of a horrid rape and murder but indicates that he likes and respects women, when the exact opposite is the case. The suspect may lie about past interpersonal and sexual experiences, alter or completely fabricate beliefs and feelings, or even exaggerate negative reactions and feelings, all in hopes of being declared incompetent or insane, and thus avoiding any responsibility. Often such exaggerations are imitations of symptoms the suspect believes will result in a well-known, though controversial, diagnosis, such as post-traumatic stress disorder, multiple personality disorder, or whatever else the suspect has recently seen in the news.

Malingering is a special form of deception in which the subject attempts to make any physical or mental defects appear worse than they actually are or to manufacture them completely. Alternatively, subjects may try to make a defect appear less severe than it actually is. Fortunately, the MMPI and several other tests include scales that indicate such deceptions.

Psychiatrists, police officers, attorneys, and many other individuals who deal with criminals and suspects on a regular basis become adept at detecting deception. There are no hard and fast rules for doing so, but several techniques, none of which are uniformly reliable, are used, including

• Looking for signs of nervousness: Many people become nervous when questioned by law enforcement officers, but sometimes signs of nervousness indicate that the person is lying. Sweating, dilated (wide open) pupils, tremors of hands and lips, failure to make eye contact, and hesitant or rapid speech can each indicate that the subject is lying.
• Reading body language: How the subject sits or moves can also betray her lies. Signs that may indicate lying include hand-wringing, slumping or slouching, finger-tapping, and fidgeting, among many others.
• Using Neuro-Linguistic Programming (NLP): NLP is a technique of reading a person’s eye movements to determine her mental state. Looking up and to the side while answering questions, for example, may indicate that the subject is recalling something she has seen. However, this technique is extremely controversial and has little scientific backing.
• Discerning micro expressions: Micro expressions are very brief changes in the person’s facial expression, usually lasting only a fraction of a second. They often result from the person attempting to repress emotions. The trick is distinguishing whether these movements are due to the natural fear many feel when talking with a psychiatrist or law enforcement officer or true deception.

Debunking the eyewitness

Eyewitnesses are notoriously unreliable. Unfortunately, memory isn’t all that reliable. Your ability to recall the details of any particular event fades with time, and the natural tendency is to fill in any blanks with what you believe should’ve happened. This unconscious effort is further colored by your personal beliefs, prejudices, motives, and expectations. Add the stress of witnessing a frightening or threatening event to these factors, and conditions are ripe for false or altered memories. Nothing malicious, just the human brain at work.

Earwitness testimony waxes (how’s that for a pun) even more unreliable. People occasionally are asked to identify a perpetrator by his voice. Unless the voice is unusual or exceptionally distinctive, this exercise is unreliable.

Dealing with false confessions

False confessions are more common than you may think. People who give false confessions don’t necessarily intend to deceive police; they may simply be confused, tired, angry, or want to get the heck out of the room. They could have psychiatric problems and actually believe they did it, or maybe they’ve fantasized about the same type of crime so many times that they can’t remember whether they did it or dreamed it.

False confessions may not make sense to you, but they happen all the time. Whenever a sensational murder is reported in the newspaper, you can be sure that about two dozen people have called police to confess to it. Go figure.

Many false confessions arise because criminals think they can deflect police from another crime. For example, a suspect may confess to stealing a car or robbing a store but claim to know nothing about the murder that occurred at the same time but in another location. If guilty of the robbery, the suspect couldn’t possibly be the killer. Likewise, a friend or family member may confess to a crime to protect the real culprit.

Some people, however, simply confess for no apparent reason. Many psychological factors come into play: low self-esteem, fear of the police, a need for fame, or a need to please the authorities or another person, for example. Many people have deep-seated feelings of guilt and may need to confess to something so they can be punished for their buried guilt, whether real or imagined.

In addition, the presence of alcohol or drugs can cloud judgment and lead to confusion, false memories, and fabrications, which in turn can make the individual unsure about whether he is guilty. With intoxicated suspects, the police may tell them that they were the only one in the house with the deceased and they may begin to believe that maybe they did commit the murder, even though they don’t remember it. This can result in a false confession.

Certain police interrogation tactics also can lead to false confessions. Isolation and fatigue can break down a person’s resolve so far that a confession seems easier than continuing with the interrogation. If interrogators employ a good cop–bad cop approach, the suspect may confess, erroneously thinking the good cop will provide protection from the bad cop and from the legal system.

Interrogators use tactics designed to trip up lying suspects. They may ask the same questions over and over in varying forms or go off on another topic and suddenly come back to a certain line of questioning. Sometimes, however, these techniques confuse innocent people to the point that a confession simply falls out of their mouth.

Determining a defendant’s competence

Competency to stand trial reflects the defendant’s ability to understand the charges, the possible consequences of the charges, the workings of the courtroom, and the roles that the judge and attorneys play. Without an understanding of these matters, the defendant can’t be fairly tried. For example, the defendant may harbor delusions that the judge is his grandfather or that the judge and attorneys are involved in a conspiracy to get him. Both delusions are counter to reality and can affect the defendant’s ability to participate in his own defense. A competency examination also determines whether the subject is competent enough to confess, testify, waive Miranda rights (the rights to remain silent and be represented by counsel), accept or refuse an insanity defense, and even to be executed.

Commonly encountered mental disorders that lead to a determination of lack of competence include

• Mental retardation, which can be due to congenital or developmental abnormalities, brain injuries, or infections
• Severe drug or alcohol addiction
• Organic brain syndromes (structural or functional brain abnormalities) such as strokes, tumors, or infections
• Severe neuroses that lead to paranoid or severe anxiety states
• Psychoses and schizophrenias accompanied by an altered perception of reality

During the trial, the forensic psychiatrist may take the stand to offer an opinion regarding the suspect’s mental state at the time of the crime and perhaps to address issues related to legal sanity, if the suspect’s defense is in the form of an insanity plea. During the post-trial, or sentencing, phase, the psychiatrist may address the defendant’s need for admission to a treatment facility as opposed to prison or may offer an opinion regarding how dangerous the defendant is or how likely the defendant is to commit crimes in the future. In death penalty cases, the psychiatrist may even be asked to comment on whether the convicted person is competent to be executed.

Defining insanity, loosely

Psychiatrists can’t diagnose insanity, because it’s a legal term rather than a medical condition. Insanity, therefore, is determined only by a judge or jury. Psychiatrists diagnose mental disorders and advise the court as to their findings, but the final say comes from the law, not medicine.

Insanity is a slippery, poorly defined term that means different things in different jurisdictions. However, most courts adhere to the McNaughten rule, which basically asks whether the suspect suffers from any mental disorder that prevents him from understanding the nature and the consequences of his actions. In other words, you can be found not guilty by reason of insanity if you didn’t know at the time of the crime that your actions were illegal or if you were incapable of altering your illicit behavior.

In 1984, Congress adopted the Omnibus Crime Code for Insanity, which states that people can be found not guilty by reason of insanity if they didn’t appreciate the illegality of their behavior. The term appreciate differs vastly from the word know, implying a higher degree of understanding than simple knowledge.

The McNaughten and the Omnibus definitions address the fact that a crime consists of two parts: the criminal activity, termed the actus reus, and criminal intent, known as the mens rea.

Diminished capacity is a special form of insanity. Its definition also varies among jurisdictions. The basic tenet of diminished capacity is that certain conditions during the commission of a crime reduced the criminal’s ability to alter his actions or to distinguish between right and wrong. In other words, the perpetrator was incapable of forming a specific criminal intent or acting in a purposeful manner.

Claiming diminished capacity is an attempt to relieve the defendant of criminal guilt or at least reduce the degree to which he is held responsible for the crime. This may simply be a defense ploy or it may indeed be true. For example, someone who kills his wife over an adulterous affair may state that he did it in a fit of rage and was not responsible for his actions (temporary insanity) when, in fact, he had planned the murder for weeks. On the other hand, an individual suffering from paranoid delusions because of chronic cocaine or methamphetamine abuse may not have been capable of planning a murder, which changes that person’s degree of liability from first-degree to second-degree murder.

Classifying the multiple murderer

Multiple murderers are people who’ve killed more than one person. Multiple murders are classified according to the location and sequence of the killings:

• Mass murderers: These killers kill more than four people in one place at one time. They often have a clear agenda and want to send a message. Mass murderers are the kind of killers who walk into their workplace and shoot several people in a rapid-fire assault. The motive often is some perceived wrong committed by co-workers or an employer.
• Spree killers: These killers kill more than one person at two or more locations. The killings are linked by motive but without a cooling-off period between the acts. Rather, the killer is constantly killing, hiding, running, or planning his next attack. Spree killers go on rampages, moving from place to place, city to city, even state to state, leaving bodies in their wake. Such sprees often end in a suicidal confrontation with law enforcement.
• Serial killers: These killers kill more than one person at different times and locations with cooling-off periods between the killings. The cooling-off periods result from the killer having satisfied the driving need behind the killings. They can last weeks, months, and even years, and allow time for the killer to unwind, come down from the high, and relax — until the demons take over again. This cooling-off period distinguishes serial killers from spree killers.

Making the monsters

Society always has difficulty understanding and dealing with serial offenders. Serial rapists and serial killers seem so far removed from the rest of society that a rational method for dealing with them has been and still is out of reach. These individuals typically are psychopaths or sociopaths, two terms that are used interchangeably. Sociopaths tend to be self-centered (egocentric and narcissistic), manipulative, emotionally shallow, and devoid of empathy and remorse. They often lie with impunity, fooling even the cleverest interrogator.

Serial rapists and serial killers have a great deal in common. In fact, they may just be at different points on the slippery slope of sanity. Many serial killers begin their adventures with rape and then progress to murder in order to cover the crime or perhaps to increase their morbid enjoyment.

The psychosexual pathology that drives these offenders appears to become ingrained early in life, and it only grows in strength as the individual matures through puberty and into adult life. Many, but not all, serial offenders come from backgrounds of physical, psychological, and sexual abuse. They may insulate themselves from this abuse by creating a protective world that’s rich in fantasy. As the fantasies develop, some serial offenders take on sexual and violent characteristics that can brew for years, or even decades, before the offender begins to act them out.

Fantasy plays a powerful role in the violent crimes of serial offenders. Early on, their fantasies may be amorphous and benign, but as they mentally play them out, again and again, year after year, the fantasies become more refined. Often the fantasies are simple, but in more imaginative offenders, they can become elaborately scripted plays. In many, sexual and violent themes tend to commingle until the two are inseparable.

When serial offenders go on the prowl for victims, they are, in fact, seeking characters in their respective fantasy plays. They may look for a certain type of person or one with a specific look. Ted Bundy, for example, sought women with dark hair that was parted in the middle; obviously they embodied the character he needed to fulfill his fantasy.

This example points out an important fact about these fantasies: They tend to be specific. Think about your own fantasies. When you daydream or fantasize about something, the details make the fantasy pleasurable, and these details typically remain the same no matter how many times you experience the fantasy. Why? Because this fantasy is comforting; it feeds some psychological need within you. So it is with the serial offender; however, serial offenders tend to have sexually violent fantasies that they may ultimately act out — and that’s a mighty big difference.

The specific details of the fantasies enable forensic psychiatrists to develop profiles of the killers. Because a killer’s fantasy is specific and repetitive, certain elements of the criminal act are also specific and repetitive. This concept shows up in the killer’s signature (see the later section about “Distinguishing MO from signature”).

Current thinking is that violent serial offenders cannot be reliably rehabilitated. This idea obviously is controversial, but one fact remains: Many laws have been placed on the books to protect the public from these criminals. They are given long sentences, and when they’re released from prison or a mental facility, they’re constantly monitored. Neighborhoods into which they move are notified of their presence.

As early as the 1930s, laws mandated that sexual offenders be evaluated and treated by medical professionals. By the 1960s, such programs were in place in virtually every state. It soon became clear to the people who were responsible for diagnosing and treating these sexual predators that they were different. These offenders neither fit into the usual diagnostic categories nor responded to the usual treatment regimens. By the 1990s, many states closed these specialized treatment centers, and longer sentences became the norm.

It is important to note that serial killers are motivated by varying drives. The nomenclature varies from expert to expert, but, in general, what I have described so far is termed a sexually sadistic serial killer. These killers are driven by sexually violent fantasies for the most part. Other types include those driven by anger (rage against a subgroup of people or society in general); profit (such as the little old lady who runs a boarding house and kills tenants while continuing to cash their support checks); power/control/thrill (those who kill for the love of the killing act); and psychosis (those driven by severe mental disorders), to name a few.

Assessing the perpetrator’s psyche

One basic method of characterizing offenders from crime-scene evidence divides them into the following three categories:

• Organized offenders: These criminals are more sophisticated in their approach, and their crimes show evidence of planning. These types tend to be of average or better intelligence, employed, and in active social relationships such as with spouses and families. Even though they’re driven by their fantasies, they maintain enough control to avoid being impulsive. They prepare and even rehearse. They tend to target specific victims or types of victims and use control measures such as restraints to maintain victim compliance. They bring the tools they need to gain access to and control of the victim and avoid leaving behind evidence. As killers, they generally hide or dispose of the body and are likely to have a dumpsite already selected.
• Disorganized offenders: These criminals usually live alone or with a relative, possess lower-than-average intelligence, are unemployed or work at menial jobs, and often have mental illnesses. They act impulsively, or as if they have little control over their fantasy-driven needs. They rarely use ruses to gain the victim’s confidence, but rather attack with sudden violence, overwhelming the victim. The crime scene often is messy and chaotic. This type of offender doesn’t plan ahead or bring tools along, but rather uses whatever is handy. As killers, they typically leave the body at the scene and exert little effort to avoid leaving behind evidence. Some even have postmortem sexual contact with the victim.
• Mixed offenders: Some offenders leave behind mixed messages at crime scenes. They show evidence of planning and a sophisticated MO, but the assault itself is frenzied or messy, which may indicate some control over deep-seated and violent fantasies.

Profilers have developed categories of descriptors, or ways that they describe the types of individuals who commit the crimes. Some of the descriptors used in serial killer profiling are

• Age: Most serial killers are in their 20s or 30s.
• Sex: Most are male.
• Race: Most don’t cross racial lines. That means, in general, white offenders kill whites, while black offenders kill blacks.
• Residency: Organized offenders are more likely to be married, have a family, and be well liked by their friends. Disorganized offenders, because of their mental instability and immaturity, tend to live alone or with a family member.
• Proximity: The location of the perpetrator’s home in relationship to the crime scene is important. Most kill close to home, a factor that is particularly true with the first few victims. The area close to home is a comfort zone. With experience, however, the killer may move his predatory boundaries farther and farther from home.
• Social skills: Killers who use a ruse to ensnare their victims, like Ted Bundy did, typically possess good social skills, whereas those who use a blitz-style attack are less comfortable with conversation.
• Work and military histories: Organized offenders more often have a stable work history and are more likely to have left any military service with an honorable discharge. Disorganized offenders often are quite simply too unstable to hold a job in the long term or to complete military service.
• Educational level: Organized offenders tend to have more schooling than their disorganized counterparts.

Using these descriptors, profilers can create a pretty good picture, or profile, of the type of person who likely committed the crime. This profile can help police home in on a specific suspect and may play an important role during the interrogation of suspects. Knowing the type of individual who’d commit a criminal act helps investigators design the right questions and leverage any pressure points during interrogation that snare suspects in a web of lies or even produce a confession.

Profiling also plays an important role in determining whether a crime scene is staged. Staging means changing the appearance of the scene so that it looks like the murder took place in a different manner and for a different reason. A classic example: the husband who kills his wife in a fit of anger, then empties drawers and closets, knocks over furniture, and breaks a door lock or window to make it appear as though a burglar committed the crime. When investigators discover that the wife was severely bludgeoned and stabbed 20 times, the light of suspicion falls on the husband. A burglar wouldn’t engage in such overkill, preferring instead to kill and run. Overkill usually is personal, with anger as the common, underlying drive.

Taking trophies and souvenirs

Many criminals take things from the crime scene. Money, jewels, electronic equipment, and other valuables that can be sold commonly are taken, as is incriminating evidence, such as the murder weapon or a used condom.

Serial offenders, on the other hand, tend to take objects that have no monetary or evidentiary value. But, regardless of what the object is, it holds some value to the perpetrator, and he will use it to relive the crime in later fantasies. Some killers take jewelry, clothing, or even driver’s licenses. Some take body parts.

Distinguishing MO from signature

Modus operandi (MO, or method of operation) describes the tools and strategies a criminal uses to commit a crime. It isn’t a new concept. It dates back to the 1880s and the efforts of Major L. W. Atcherley, a police constable in the West Riding Yorkshire Constabulary in England, who developed a 10-point system for identifying a perpetrator’s MO. Scotland Yard later adopted many of his techniques.

Atcherley considered the following factors:

• Location of the crime
• Point of entry
• Method of entry
• Tools that were used during the crime
• Types of objects taken from the crime scene
• Time of day the crime was committed
• The perpetrator’s alibi
• The perpetrator’s accomplices
• Method of transportation to and from the scene
• Unusual features of the crime, such as killing the family dog or leaving behind a note or object to taunt the police

All these factors address the perpetrator’s method of doing things. They are the things the killer sees as necessary to committing and getting away with the crime.

An MO often evolves over time as the unsub finds better ways to commit the murders or other crimes and to avoid detection. Perpetrators change their mode of entry, ruse, disguise, when and where the attacks take place, and whatever else makes their efforts more effective.

In contrast to an MO, a signature is an act that has nothing to do with completing the crime or getting away with it. Signatures are important to the offender in some personal way. Torturing the victim, overkill, postmortem mutilation or posing, and the taking of souvenirs or trophies are signatures. These actions are driven by the killer’s psychological needs and fantasies.

Unlike an MO, a signature never changes. It may be refined over time, but the basic signature remains the same. For example, if a serial killer poses victims in a religious manner, praying or as a crucifix, details such as candles, crucifixes, or other ceremonial objects may be added later. The signature has changed, but its basic form and theme remain the same.

The reason for the stability of the signature lies in its driving force. The signature is derived directly from the unsub’s fantasies. These fantasies develop early in life and are refined into an obsession from years of mental reenactment. During the crime, an unsub forces the victim to respond according to the script from his fantasy. The signature is solely for the killer to live out his personal fantasy. Because the fantasy never changes, the signature remains intact.

Profiling the victim: Victimology

Evaluating the victim often adds to the offender profile. Studying victim characteristics is called victimology, which basically is establishing a measure of their risk of becoming a victim as a result of their personal, professional, and social life. A detailed understanding of the victim’s lifestyle and habits provides clues as to why this particular victim was selected at a given time and location. This information divides victims into the following risk categories:

• High-risk victims frequently live in high-risk situations. Prostitutes, particularly the ones who walk the streets, obviously fall into this category. They typically work at night, interact with strangers on a regular basis, willingly get into cars with strangers, and thus are easy targets. Other high-risk behaviors include drug use, promiscuous lifestyles, nighttime employment, and associations with people who possess criminal personalities.
• Low-risk victims stay close to work and home, don’t visit areas unfamiliar to them, and lock their doors at night. They have steady jobs and many friends.
• Medium-risk victims fall between these two extremes. A medium-risk victim may work close to home and lock her doors but be promiscuous and occasionally venture out at night alone.

Offenders select their particular victims based on their fantasies and the victims’ vulnerability. Some victims merely are grabbed as victims of opportunity. High-risk victims place themselves in vulnerable positions much more often than low-risk victims, but either can simply be in the wrong place at the wrong time. Other victims are taken because they fit the starring role in the perpetrator’s fantasy. Offenders may spend days or weeks cruising for just the right victim, the one who most closely matches the perpetrator’s fantasy. Other potentially easy victims are ignored because they’re just not right.

A special form of victim profiling is the psychological autopsy, which is performed when the manner of a victim’s death isn’t clear, that is, investigators don’t know whether the victim’s death was an accident, suicide, or homicide. To help make this determination, the forensic psychiatrist looks into the victim’s medical, school, work, and military histories; interviews family, friends, and associates; and evaluates autopsy, police, and witness reports. The goal is to assess whether the victim was the type of person who was living in a stressful enough situation to commit suicide or living a lifestyle that made the victim an easy target for a killer.

Drawing boundaries: The killer’s domain

You’ve no doubt watched nature shows on TV where the narrator discusses a certain predator’s domain or hunting range. Game wardens use these boundaries to narrow their searches for elusive lions or tigers. Profilers do the same with serial killers.

Analysis of the pattern of the perpetrator’s assaults can yield valuable information that ultimately leads to the apprehension of the assailant. Known as geographic profiling, this technique is based on the premise that serial offenders, like lions and tigers, have certain comfort zones within which they feel free to carry out their crimes. The geographic profiler likes to know where the victim was abducted, where the actual assault or murder took place, and where the body was dumped. Whenever several assaults have occurred, profilers have several such locations with which to work and can then locate the points on a map and thus define the killer’s domain.

The killer’s domain may show murders clustered in a small area, which may indicate the killer isn’t very mobile and thus may not possess a car or have a job. Conversely, if the range is broad, the perpetrator likely is highly mobile and possesses a vehicle with high mileage from its use to troll for victims. Regardless of whether the range is narrow or broad, the perpetrator likely resides or works within or near this comfort zone.

In general, disorganized killers, because of their inability to hold a job, maintain social connections, or make sophisticated plans — as well as their mental illness — tend to have narrower comfort zones and thus more confined boundaries. Organized killers are able to plan and travel and as a result tend to have much larger domains.

Determining which victim was killed first is important for investigators because the comfort zones for most serial killers usually begin small and grow with each killing. The first victim probably was abducted closer to the killer’s home or workplace.

Determining the order of the crimes is straightforward if the victims are found shortly after the crime. However, if the victims are street dwellers or prostitutes, whose disappearance may go unnoticed, the dates of their abductions may not be known. Likewise, if the bodies are dumped in remote places, the order in which the victims were killed may not be the order in which the bodies are found. In such cases, a forensic anthropologist may be brought in to assess approximate times of death. Having this knowledge can be crucial in identifying the killer.