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At face value, the FBI's approach sounds highly intuitive and appealing.
However, one major issue with it is that it is unclear, aside from the original study
conducted by interview with serial sexual murderers, how these associations between crime scene characteristics
and offender characteristics have actually come about.
Traditionally, the FBI in their accounts have placed great emphasis on their investigators'
field experience and they cite this as the key factor that underpins the associations that they assert.
So a key question is how well do these profilers actually perform?
Although there have been many anecdotal examples and unpublished reports claiming the success
of the FBI's method of profiling, there are, in fact, very few published empirical
analyses and each of these are controversial in their own way.
However, as an illustrative study, we will go back to one of the first. And these were
conducted by Anthony Pinizotto with the collaboration of the FBI. In a paper published in 1990,
Anthony Pinizotto and Norman Finkel sought to determine whether professional profilers
were more accurate than non-profilers in generating personality profiles and correctly identifying
offender features from crime scene details.
They also wanted to explore whether the processes used by the profilers was qualitatively different
from the processes used by the non-profilers. Now in total they had 28 participants who
were categorised on the basis of their profiling expertise. We are going to concentrate on
just 24 of those participants. These were 6 police detectives who made up the PROFILERS
group. That is, they had all been specifically trained in profiling. They had completed a
1-year program through the FBI Behavioral Science Unit and they had a range of 1-6 years
experience in actually profiling.
The second group were the group of DETECTIVES. This group was made up of 6 detectives from a large metropolitan
city police department. Now these officers had no training in profiling, but they were
experienced police investigators in homicide and sex offence cases
(which were the two crimes chosen for this study).
The third group were a group of clinical PSYCHOLOGISTS and the fourth group was a group made
up of STUDENTS. In each of these were 6 participants who met the criteria and they were selected
as non-police participants who were both naive to profiling and criminal investigations.
All participants were given materials from two closed cases; that is these crimes
had actually already been solved. One case involved a homicide and the other a sex offence.
In both cases participants were provided with information about the victim
and also the crime scene reports.
So for the sexual offence, it detailed the events leading up to the offence, what actually
occurred in the offence itself, and the events that followed the offence. In addition,
in this case, participants also read a detailed victim statement, what happened and what
the offender did and said.
Now in the homicide case, participants were given 14 black and white crime scene photos.
They were also given autopsy and toxicology reports. Now these detailed the cause,
the manner and the mode of death. The toxicology report showed whether there were any chemical
agents present in the victim's system at the time of death that may have caused or
contributed to the death.
Now in both cases, and in order to protect the identity of the victim, some information
that would normally be available to profilers, such as maps of geographical areas where the
crimes took place, were actually absent.
So all participants read both cases and they balanced the order, so some read the homicide
case first and the others read the sexual offence case first. Now after they read each case,
they were asked to cover the material and write down as many details about the case
that they were able to remember.
They then had to use this to note down all the details from the crime scene that they
felt were necessary and important to be used in writing a profile about the type of person
of would commit such a crime, and also note down why they felt these facts were important.
They were also then asked to write a profile of the type of person who committed the crime,
and to give as much detail as possible, and then they had to record this onto audiotape.
Finally they were given a multiple choice question sheet. This consisted of 20 questions
about the suspect (questions about their age, their gender, their residence, their employment).
Now 15 of these could be scored as being correct or not.
And as a very last step they completed a line up task. Participants were given five descriptions
of possible suspects and they had to rank order them from 1 (the suspect they thought
who was most likely to have committed the crime) down to 5 (the person least likely to have
committed the crime).
So what did they find on these measures? Well, the analysis indicated that profilers provided
richer and longer reports than the non-profilers in terms of number of the predictions, for example.
Critically, however, they also provided significantly more accurate predictions in both cases.
Profilers were significantly more accurate than the non-profiler groups.
However, when their responses to the multiple choice questions were analysed, profilers
only scored significantly better than the other three groups combined for the sexual
offence case.
Similarly when looking at the line up results, the superior ability of the profilers to identify
the correct offender only emerged in relation to the sexual offence. It didn't emerge
on either measure in the homicide case.
Finally when looking at how profilers used the information they were given, to see if
the way they used it differed from how other participants used the information, they found
no evidence that the profilers assessed the information in qualitatively different way
from the non profilers.
So this study gives us a mixed picture of profilers of how profilers actually perform. Professional profilers provided
richer profiles, they made more accurate predictions in their written profiles than participants
belonging to the other groups.
Further, professional profilers were more accurate in terms of multiple choice responding
and in picking out the perpetrator from a line up for the sex offence case than non
profilers, but those accuracy differences were not seen in the homicide case. Here profilers
performed just as well, or rather, just as poorly as detectives, psychologists and students.
So why? Was the version of the homicide case just too sanitised? All the profilers noted that
information they'd expected to see when constructing a profile was actually missing in this study.
Or was it more to do with the fact that the homicide offender did not fit the base rates
in all ways? And this shows an inherent problem in profiling. What if your offender
isn't a statistically normal or a 'typical' offender?