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Thursday, July 22, 2010

PSYC 3402: Serial Homicide

This post contains a lot of information from the book.

Also, relevant news on Robert Pickton and how the rest of the 20 (of 26) murder charges were stayed.

1. Aggression and Violence

Aggression: any behaviour directed towards another individual that is carried out with the proximate (immediate) intent to cause harm; the perpetrator must believe the behaviour will harm the target and that the target is motivated to avoid the behaviour.

  • Hostile Aggression: impulsive reaction to some real or perceived provocation or threat (same proximate and ultimate goal).
  • Instrumental Violence: premeditated and aimed at achieving some secondary goal, such as receiving payment (different proximate and ultimate goals).

1.1 Prevalence of Violence (Trends)

Kitten and dog fight

The following outlines some of the observed trends since the 1990s, focusing on violent crimes:

  • Violent crimes and robbery have been steadily decreasing since early 1990s (though robbery without a weapon has been increasing slightly).
  • Violent crime by youth has increased steadily since the 1990s.
  • According to the General Social Survey on Victimization (GSS), only 33% of violent incidents were reported in 2004, with reporting rates highest for robbery and physical assaults.
    • Crimes that involve physical injury or weapons are more likely to be reported to police.
    • Victims are most likely not to report crimes because they dealt with it another way, it wasn’t important enough and/or they didn’t want the police involved (among other reasons).

1.2 Victim Characteristics

The victimization rates for men and women are similar but…

  • Men are more likely to experience non-sexual violence and women are more likely to experience sexual violence.
  • Half of violent crimes are committed by friends/acquaintances/family and 44% are committed by strangers.
  • Victim Profile: young (15-24), single, going out in the evening (bars, visiting friends) and living in the cities (this is you, University student); the older you get, the less you are victimized.
  • 25% of violent crimes resulted in physical injury to victims (30% of those were robberies and 30% were physical assaults).

2. Explaining Violence

Read more on Operant Conditioning, and Bandura’s Vicarious Conditioning.

2.1 General Aggression Model (GAM)

GAM: describes the process of our internal decision-making process during a social encounter. This theory is often discussed in the context of exposure to violence in video games and the media.
The process begins with two types of inputs:

  1. Person (traits, gender, beliefs, etc) and
  2. Situational Factors (aggressive cues, provocation, frustration, etc).

These inputs influence our internal state via three routes: cognition, affect and arousal. These routes are inter-related and can impact each other, influencing how we respond to the social encounter (aggressively or not).

You appraise the information and decide how you’ll act (thoughtfully or impulsively), which influences the social encounter, influencing the person and situation inputs! (Circular theory)

2.2 Evolutionary Psychological Perspective

Evolutionary Psychological Perspective: suggests that most violent people fall into one of three categories:

  1. Young men (most common): young men tend to have lower status and fewer resources so it puts them at a competitive disadvantage compared to other men competing for the same resources and mates. By turning to violence, they can raise their status and increase their chances of finding a good mate. As they age, the costs of violence outweighs the benefits and they begin to look for lower-risk, long-term solutions (as more legitimate means of achieving status and success appear).
  2. Competitively Disadvantaged Men (life-course persistent): these men are disadvantaged because they don’t have the skills or abilities to achieve status and resources in prosocial ways, so they maintain their risky behaviour throughout adulthood.
  3. Psychopaths (life-course persistent): these men select short-term high-risk strategies as an alternate approach.

3. Risk Assessment

FYI: put little emphasis on this section for the exam. Focus on what they’re designed to assess – the more I know about a topic, the easier it is to remember the main points, which is why this section contains more information than needed.

There are three major types of assessment tools:

  1. VRAG (Violence Risk Appraisal Guide): an actuarial risk assessment instrument designed to assess the long-term risk for violence recidivism in offenders with mental disorders by examining certain static risk factors (such as the PCL-R score, elementary school maladjustment, personality disorder etc), scoring them and placing them in one of nine risk bins (higher scores = higher risk).
    Disadvantage: not transparent or idiographic.
  2. HCR-20: a structured professional judgment instrument designed to assess the risk of violent behaviour with 10 Historical factors, 5 Clinical factors and 5 Risk management factors. The presence of the risk factors is calculated and then we subjectively decide on the level of risk based on case-specific risk factors.
    Risk Ratings:
    • Low Risk: monitor and intervene with low priority and intensity.
    • Mid Risk: monitor and intervene with some priority and intensity.
    • High Risk: monitor and intervene with high priority and intensity.

    Results: moderate to strong prediction of violent recidivism.
  3. SAQ (Self-Appraisal Questionnaire – no liquor): a self-report actuarial instrument design to estimate the risk of violent and non-violent recidivism. The questions fall under 6 categories: criminal tendencies; antisocial personality problems; conduct problems; criminal history; alcohol-drug abuse; and antisocial associates (higher scores = higher risk). Two subscales were added (Anger and Validity) in order to assess the degree to which anger is present (so we can address it) and how trustworthy the responses were.
    Advantage: quick and easy to fill out.
    Disadvantage: reliability of responses (offenders will respond in socially desirable ways) and answers may lack insight (a lack of self-awareness of their behaviour may bias their responses).

Mental Disorders: on the VRAG, mental disorders are considered a risk factor but on the HCR-20, schizophrenia is considered a protective factor.

Why the difference? If we focus on the entire population mental disorders are more likely to be violent than people without mental disorders. When a person feels like their self-control is overridden by forces beyond their control, or they feel like they’ll be harmed by others, they’re more likely to engage in violence (threat/control override).

But if we’re looking at the population of offenders or forensic psychiatric patients, mental disorders don’t predict violent recidivism but also don’t predict reduced violent recidivism (it neither increases nor decrease the likelihood of violence).

4. Treatment and Management

4.1 VPP (Violence Prevention Program)

VPP: an intensive cognitive-behavioural reintegration program for incarcerated federal offenders, emphasizing violence prevention.

  • Target Group: designed for offenders who’ve committed at least 2 violent offences or are at a high-risk to commit a violent offence.
  • Goal: to improve the skills of participants (self-control, social problem-solving, education, self-management) and subsequently reduce the risk of future violence.

4.2 Evaluating Treatment Effectiveness

Treatment is better than sanctions (we know this already) but the effectiveness of the treatment depends on three factors: who is treated, what is treated (incorporating ECTs is best, but you can read more in the Offender Treatment lecture) and how treatment is delivered.

Research suggests:

  • Treatment for violent offenders is associated with lower rates of violent recidivism.
  • Treatments that include anger management, cognitive skills, role play, relapse prevention, and/or homework are associated with lower rates of violent recidivism.
  • Treatments delivered by correctional or probation officers were significantly associated with reductions in violent recidivism (as opposed to being delivered by psychologists or other rehabilitation professionals).

Read the book for why you have to be careful to draw conclusions from these results.

5. Extreme Forms of Violence

5.1 Types of Homicide

Homicide has been declining since the mid 1970s; western and northern provinces have the highest rates. Gang-related homicides have been steadily increasing since the early 1990s.

There are four major types of homicide:

  1. First-degree Murder: murder that is planned and deliberate; or if the victim is a peace officer or prison employee; or if the victim’s death is caused while committing or attempting to commit plane hijacking, sexual assault, kidnapping, hostage taking, criminal harassment, terrorist activity, use of explosives in association with a criminal organization or intimidation.
  2. Second-degree Murder: everything that’s not first-degree.
  3. Infanticide: where a woman, who has not fully recovered from the effects of birth so her “mind is disturbed”, kills her child (because her mind is disturbed).
  4. Manslaughter: murder committed in an act of passion or sudden provocation; or a death resulting from criminal negligence.

5.1.1 Mass Murder

Mass Murder: three or more victims are killed during one event, in one location with no emotional cooling off period between murders. The reason behind them is believed to be to take back control over themselves and their situation.

Additional Characteristics: these are not required but they are commonly present…

  • Handguns or semi-automatic weapons are preferred;
  • Primary victims are pre-selected;
  • Not necessarily premeditated – debate over this;
  • Occurs in public places with the exception of family killers;
  • These are more’ understandable’
  • The mass murderer is unconcerned with their inevitable capture or death and often ends in suicide.

5.1.2 Spree Murder

Spree Murder: where three or more victims are killed in three or more locations over a period of less than 30 days with no emotional cooling off period between murders. The murder is also accompanied by the commission of another felony, such as armed robbery (high excitation level driven by drugs or a mental illness).

5.1.3 Serial Murder

Serial Murder: the killing of three or more victims on three or more separate occasions over a period of more than 30 days with an emotional cooling off period between each homicide. This is the most commonly accepted definition.

Additional Characteristics: these are not required but they are commonly present…

  • Three or more separate locations
  • Premeditated
  • Offence-related fantasy and detailed planning
  • Motive: the thrill of killing another human being
  • Victim is killed during a one-on-one encounter
  • Serial murder is rarely a crime of passion or for personal gain

Issues Defining Serial Murder: the single most critical stumbling block exists at the definitional level

  • Motive: should it matter and how? (ex: think about Contract Killers and Soldiers – we wouldn’t assign them the “serial killer” title, which varies significantly from instrumental murders) Tends to be an internal motivation (no explicit revenge, no monetary gain), normally curiosity, excitement, power and sex.
  • Number of victims: how many? How do we determine this number?

US Statistics: we must take into account the definition problems mentioned above when we are looking at the statistics.

  • 331 serial murderers were operating in the U.S. between January 1977 and April 1992 according to NCAVC (FBI).
  • It has been estimated that 2% of the homicide victims each year are the result of serial killers.
  • Estimated that 30 to 50 Serial Killers are operating in the US at any one time.
  • Take-Away Point: nobody knows.

Canadian Statistics: less common in Canada than in the US; estimated range is between 5 to 30 serial killers active at any one time – perhaps because we have fewer cities.

Characteristics of Serial Killers

Profile of Killer and Victim: Exam Note: don’t focus on this for the exam.

  • Killer: 25-35 years old, male, predominantly Caucasian (80%) in the US and normally kill intra-racially.
    • Common Background Elements: rejection, unstable home, physical abuse, mental/emotional abuse, divorce and an alcoholic parent.
    • Additional Characteristics: tend not to be highly educated or hold professional or skilled career, many are ‘police-groupies’, ‘street smart’, often use a ruse or con, focus on one type of victim (IVT – Ideal Victim Types), and have antisocial qualities/psychopathic (ex: charming, charismatic). They also have a criminal history and use alcohol/drugs (in order to cope with the dead bodies).
  • Victim: usually younger and female.
    • Additional Characteristics: stranger, tend to be alone (occupational risks in particular, such as nurses, models, waitresses, prostitutes).

Geographic Variation: there are three types of geographically-based serial murders…

  1. Geographically Transient (35%): where the serial killer kills victims in more than one state; these offenders are believed to kill more victims and choose this method to avoid detection (linkage blindness - ViCLAS). (Ex: Ted Bundy)
  2. Geographically Stable (55%): these killers never leave their states or surrounding cities. (Ex: Paul Bernardo)
  3. Place-Specific (10%)
Female Serial Killers

Female serial killers aren’t often included under the traditional definition of serial homicide even though they meet the requirements because of a few reasons…

  • Not usually sexually involved with victims;
  • Not viewed as physically or psychologically capable (they are viewed as nurturing and vulnerable);
  • Not nearly as prevalent as male serial homicide, but has been on the rise since 1970 (17%).

Profile: they tend to be between 20-30 years old, Caucasian (97%), and a homemaker (Black Widow) or nurse (Angel of Death).  They most commonly commit Place-Specific kills (62%); tend not to have a criminal history; and at least 50% experienced some form of physical, emotional or sexual abuse.

Additional Characteristics: most common is poison; they don’t engage in mutilation, torture or dismemberment; they don’t stalk their victims; victims tend to be latent (elderly, children, and mentally ill). Fifty percent have a male accomplice.

The table below summarizes the main differences between male and female serial killers.

Exam Note: understand and list the differences between male and female killers.

Table 1. Differences Between Male and Female Serial Killers
  Male Female
Monikers (labels the media give them) Scary, intimidating names to serial killers Less scary, friendlier names
Sentencing Harsher sentences Less harsh sentences
Geographic Mobility Transient More likely to be place-specific
Methods Firearms, strangulation, stabbed (more hands-on) Poison, shooting (less involved in the crime)
Motives Sex, control, money, enjoyment Money, control
Victim Types Strangers, acquaintances Family
Serial Killer Typologies

Take-Away Point: current research supports no typologies.

There are four major types of serial killers: visionary (psychotic), mission-oriented (demon- or God-mandated), hedonistic (for lust, thrill or comfort), and power/control.

Organized-Disorganized Model

Organized-Disorganized Model: a theory where the offender’s background and crimes can be classified as organized (self-control/methodical and well-planned) or disorganized (impulsive/psychopathic and chaotic) and that there is a link between the crime scene and the background.

Table 2. A Comparison of an Offender's Organized and Disorganized Crime and Background
  Organized Disorganized
Offence Behaviours (Crime)
  • Planning
  • Use of restraints
  • Ante-mortem abuse
  • Use of vehicle
  • Control of victim
  • Evidence is left
  • Position of the body
  • Post-mortem abuse
  • Keeps body
  • No vehicle
Offender Characteristics (Background)
  • Intelligent
  • Skilled in job
  • Decent car
  • Follows media
  • Sexually ignorant
  • Knows victim
  • Lives alone
  • Lives close to crime
Criticisms of Organized-Disorganized Model

The bulk of the research suggests that most offenders fit both profiles to some degree (organized and disorganized). Here are 5 major criticisms:

  1. Circular Reasoning for Case Assignment
  2. Biased Sample: volunteers in a prison – you have to question why they’re volunteering and how they differ from those that aren’t volunteering.
  3. Cross-Cultural Generalizability:
  4. Prevalence of Mixed Crime Scenes: most offenders and crimes fit into both the organized and disorganized category.
  5. Theoretical Underpinnings: the ‘classic trait’ model is used to infer traits and behaviours about a person in order to predict future behaviour; these predictions are dependent on stable traits which have been proven to be not the case.

And from PSYC 2400:

  1. Ambiguous Advice: (Barnum Effect – cold readers) often the way a profile is written can be interpreted in many different ways.
  2. Myth of the Expert: professional profilers show no significant increase in profiling effectiveness over detectives, and university students (and regular Joe-Blows).

And here’s the FBI’s response to these criticisms: because their profilers are in high demand, they believe that their techniques are justified – they also downplay the need for empirical evidence.

Attempt to Validate Organized/Disorganized Dichotomy: using 100 cases of US serial killers, they coded for 39 CS variables; they were interested in the degree to which they commit co-occurring crimes  (essentially, the likelihood that certain organized behaviours occur with other organized behaviours).

  • Results: organized, disorganized and mixed all tends to correlate (~0.5) which means that there’s a whole bunch of co-occurrence across all types of behaviours (which means the FBI is wrong to use the O/D Model).
  • Most offenders are organized but it’s the type of disorganized behaviours that distinguish them from each other.

Three Most Important Factors Used in the Classification of Serial Murder:

  1. Victims: specific vs. non-specific; random vs. non-random; affiliate vs. stranger.
  2. Method: act vs. process-focussed; planned vs. spontaneous; organization of the event.
  3. Location: geographically stable; geographically transient.

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