Homicide Profiling Index- Revised (HPI-R)

(Definition, categories, variables, coded for)

coding dictionary designed for use with police case files

=Assaults, Homicide, Rape, Theft-behaviors

IP made the HPI-R

300+ Variables. Pre/post crime behaviors, location, victim and offender demographics, narative

Presence, Absence, Unknown, Unclear

Purpose: Classification

 Individual Differentiation of crime scenes

Offender background Consistency

A -> C Equation Link crime scene types to offender types

Used SSA and Feschback Instrumental/Expressive theory

Expressive = victim important. Instrumental = Victim is vehicle to other goal

Expressive/Instrumental Crime Scenes and Conclusion (Salfati 2000)

(Behavior types in different ranges, common factor for each, and conclusion)

Expressive Behaviors:

30-50 Extreme physical attack- wounding behaviors

30-10 Offenders were prepared - bring weapon

<10 Separate themselves from the victim/crime scene

Taken together they suggest offender and victim knew each other to come extent. The victim is VERY important.

Instrumental Behaviors:

Behaviors not directed at person- rather towards attaining ulterior motive- money/sex

((30-50 wounding; 10-30 theft and sexual assault/ulterior motive; <10 sexual subset))

Conclusions:

Understanding behaviors together gives different meanings than looking at them alone. The co-occurence reflects the type of relationship between the victim and offender and the importance of the victim

Expressive/Instrumental Offender Backgrounds (Salfati 2000)

(Types of background characteristics for each)

Same expressive/instrumental split

Expressive: History of difficulty with personal relationships, deal with people and situations as having a direct emotional impact on them. Victim is a specific person

Instrumental: Dealt with offenders previous criminal histories- theft/burglary/sexual; unemployment

Linking Crime Scene to Characteristics

Checked her validity

2 times criteria: case must have two times as many expressive behaviors/characteristics than instrumental (or vice versa)**

Explicit instructions on classification

(She had nothing to go on, completely new ideas, so she did it to recognize that offenders may react to the situation and there may be overlap of behaviors, also because it was a brand new classification)

Hybrid cases: roughly the same # of expressive and instrumental variables

(testing validity of model and providing specific instructions)

(expressive crime scenes can be committed by instrumental offenders, could only classify 50% accurately, and 2x criteria seems arbitrary)

(The fact that she tested her model was HUGE)

Purpose: identify how profilers differ from others in their assessments and predictions of perpetrators.

Type of information contained in profiles

Method: Compared five different groups

Psychics, graduate psychology students, biology college students, police officers, profilers

Results: 

Profilers: longer and more detailed reports; more information about non-physical aspects of offender. More knowledge of research/classifications used for profiling

Psychologists and profilers provided the most information about behavioral aspects of crime

Skills of psychologists and profilers are similar

Purpose: Test the FBI’s assumption of what makes a good profiler.

Group: Psychologists, police officers, science and econ students, psychics, and profilers

Results: No differences between the groups in overall accuracy. Collapsing non-profiler groups together- profilers are more accurate than non-profilers.

Psychologists were better than police.

Conclusion: 

Profilers more accurate than non-profilers.

Psychological knowledge is more pertinent to profiling than investigative experience or intuition

K2000 purpose was to test the FBI assumptions about what makes a good profiler, '03 was to find out how profilers differ from others in assessments 

2003: Profilers better than non-profilers. Psychologists did well.

2000: Skills  of psych and profilers similar. Psych knowledge is more pertinent to profiling than experience or intuition

Purpose: Classification

 Individual Differentiation of crime scenes

Offender background Consistency

A -> C Equation Link crime scene types to offender types

Used SSA and Feschback Instrumental/Expressive theory

Expressive = victim important. Instrumental = Victim is vehicle to other goal

Expressive/Instrumental Crime Scenes and Conclusion (Salfati 2000)

(Behavior types in different ranges, common factor for each, and conclusion)

Expressive Behaviors:

30-50 Extreme physical attack- wounding behaviors

30-10 Offenders were prepared - bring weapon

<10 Separate themselves from the victim/crime scene

Taken together they suggest offender and victim knew each other to come extent. The victim is VERY important.

Instrumental Behaviors:

Behaviors not directed at person- rather towards attaining ulterior motive- money/sex

((30-50 wounding; 10-30 theft and sexual assault/ulterior motive; <10 sexual subset))

Conclusions:

Understanding behaviors together gives different meanings than looking at them alone. The co-occurence reflects the type of relationship between the victim and offender and the importance of the victim

Expressive/Instrumental Offender Backgrounds (Salfati 2000)

(Types of background characteristics for each)

Same expressive/instrumental split

Expressive: History of difficulty with personal relationships, deal with people and situations as having a direct emotional impact on them. Victim is a specific person

Instrumental: Dealt with offenders previous criminal histories- theft/burglary/sexual; unemployment

Linking Crime Scene to Characteristics

Checked her validity

2 times criteria: case must have two times as many expressive behaviors/characteristics than instrumental (or vice versa)**

Explicit instructions on classification

(She had nothing to go on, completely new ideas, so she did it to recognize that offenders may react to the situation and there may be overlap of behaviors, also because it was a brand new classification)

Hybrid cases: roughly the same # of expressive and instrumental variables

(testing validity of model and providing specific instructions)

(expressive crime scenes can be committed by instrumental offenders, could only classify 50% accurately, and 2x criteria seems arbitrary)

(The fact that she tested her model was HUGE)