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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  • Although there have been many anecdotal examples and unpublished reports claiming the success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?

At face value, the FBI's approach sounds highly intuitive and appealing.

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B1 中級 美國腔

1.3專業剖析師好嗎? (1.3 Are Professional Profilers Better?)

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    kismet 發佈於 2021 年 01 月 14 日
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