Skip to search form Skip to main content You are currently offline. Some features of the site may not work correctly. DOI: The aim of the present work was to analyze emotional expressions in true and false victims with moderate and light intellectual disability ID with no specific etiology. View via Publisher.

Author:Meztizil Dilrajas
Language:English (Spanish)
Published (Last):1 July 2008
PDF File Size:13.55 Mb
ePub File Size:8.69 Mb
Price:Free* [*Free Regsitration Required]

Antonio L. The objective of this study was to analyze the features that distinguish statements given by actual and simulated victims with mild to moderate intellectual disability, using the credibility analysis procedure known as Reality Monitoring RM. Two evaluators trained in credibility analysis procedures using content criteria evaluated 13 true statements and 16 false statements. The results obtained show that there is little difference between the two types of statements when analyzed on the basis of content criteria using the RM procedure.

The only criteria that proved to be significant for discriminating between the two types of statements were the amount of details and the length of spontaneous statements obtained through free recall. None of the phenomenological characteristics studied turned out to be significant for discriminating between actual and simulated victims.

Graphic representation using high-dimensional visualization HDV with all criteria taken into consideration shows that the two types of statements are quite heterogeneous. Cluster analysis can group cases with a Key words: Credibility assessment; intellectual disability; content criteria; eyewitness testimony; high-dimensional visualization.

Los resultados encontrados muestran que existen pocas diferencias entre los dos tipos de relatos. Peled et al. Half of the observers were told beforehand that the witness had moderate intellectual disability, and the other half were told that the witness was a person who was developmentally normal.

When subsequently questioned about the credibility of the testimonies, they stated that those testimonies given by a person with ID were considered less credible. Henry et al.

They found no correlation between the credibility evaluations and either mental age or anxiety. Such procedures do not exist at this time, however, which means that persons with ID are often excluded from the justice system or evaluated on the basis of a comparison with children.

Forensic psychology has proposed various procedures for evaluating credibility through analysis of statement content Manzanero, RM's basic assumption is that statements based on memories of actual events are qualitatively different from statements that are not based on experience or are simply the product of fantasy, as Johnson and Raye had shown.

According to the original proposition, actual statements would contain more contextual and sensory information and show less allusion to cognitive processes and idiosyncratic information than fabricated statements.

In a first approximation, Johnson and Raye proposed that there are four types of essential attributes by which we could differentiate between the two types of information stored in memory. Memories of perceptive origin would have more contextual and sensory attributes and more semantic details, while self-generated memories would contain more information about cognitive operations.

As subsequent research was expanding the list of differentiating attributes see Table 1 , the data was showing, simultaneously, that the presence of these distinctive features depends on the influence of a host of factors. On the other hand, the wide variability in memory origin means that the characteristics differentiating fantasies, lies, dreams, and post-event information are not the same.

Even for each modality, however, there are varying degrees of remove from the actual information. For example, changing a small detail of an actual event-even a very important detail, such as whether the role played in the event was witness or protagonistis not the same thing as fabricating the entire event Manzanero, In any case, false statements are never entirely fabricated but originate, in part, from information perceived from different sources that is re-elaborated to create a new statement.

Likewise, characteristics of the statements could vary in relation to the participant's ability to generate a plausible statement. We are not aware, however, of any study on the characteristics that differentiate true statements from false statements in this population. This was the reason for conducting the following experiment: to analyze the differences between statements given by actual and simulated victims with ID, using the features proposed under the framework of Reality Monitoring RM processes-the ultimate purpose being to develop procedures adapted for these victims.

The hope was that similar results would be obtained in this study. Twenty-nine persons with intellectual disability participated in the study. Thirteen of the participants were actual victims, with a mean IQ of To conduct this research, a real event was chosen that happened two years ago-a day trip taken by a group of persons with ID from the Carmen Pardo-Valcarce Foundation, during which the bus they were traveling in caught fire.

A researcher selected the participants, all of comparable IQ, on the basis of criteria for the "true" group-did go on the day trip-and the "false" group-did not go on the day trip but knew about the event from references made to it. All persons with ID who participated in the study or their legal guardians signed a consent for voluntary participation. Each of the persons with ID was given instructions and informed of the purpose of the research.

In addition, those participants who did not go on the day trip were given a summary of the most important information about the trip, such as the location, the trip's primary complication, and how the day went. We increased the ecological validity of our study by encouraging all participants in the two groups to do their best when giving their testimony.

However, to avoid putting them under too much pressure to make the interviewer believe their testimony, we chose an incentive that was not stressful-they would be invited for a soda if they succeeded in convincing the interviewer that they had, in fact, experienced the event. In addition, the persons with ID who belonged to the false statement group were told explicitly that they had the option to lie and were assured there would be no negative consequences if they did so, thereby preventing undue tension.

Two "blind" researchers, experts at interviewing and taking testimony, interviewed each participant individually. An audiovisual recording was made of all interviews. The same instructions were given for all interviews conducted: "We want you to tell us what happened when you went on the day trip and the bus caught fire We want you to tell us even things that you might think are not very important.

Where was it? Where were you going? What did you yourself do? The interviews were conducted in random order. The interview tapes were transcribed to facilitate analysis of the phenomenological characteristics of the statements, with any reference to the participant's group eliminated.

Two trained evaluators assessed each statement individually on each of the content criteria proposed in the RM procedure see Table 2 , and then an interjudge agreement was reached. For correcting amount of detail , a chart was made of the micropropositions, describing as objectively as possible what happened in the actual event.

All measurements, with the exception of length , were measured by counting the number of times each one occurred in the statements. There were no significant effects on the rest of the criteria. Table 2 shows the mean scores and standard deviations for false statements and true statements and the totals for each criterion. As a way to appreciate the differences between the two types of statements, with all the measurements analyzed taken into consideration, the data was represented graphically through a high-dimensional visualization HDV technique used in other studies Buja et al.

As may be appreciated from the graph in Figure 2 , one possible explanation for the scant difference between the two types of statements stems from intersubject variability, which would indicate that this technique has low diagnostic capability.

If we tried to classify the two types of statements based on all the phenomenological characteristics considered in the RM technique, K-Means Cluster Analysis grouped 25 cases as false and 7 as true. When cluster A is considered equal to simulation and B equal to actual, the false statements were correctly classified in 16 cases As may be observed in HDV graph, the main reason is that the actual victims' statements are more heterogeneous than the simulated victims' statements-for those of the former group are, phenomenologically, more similar to those of the latter group, in some cases.

As noted in the introduction, there is an abundance of literature that points out inconsistencies in the attributes differentiating true statements from false statements, as well as the irrelevance of RM procedure criteria, on the whole, for distinguishing between true and false statements. Likewise, from the results obtained in this study, we can conclude that the above-mentioned technique is also not valid for distinguishing between statements given by actual and simulated victims with ID.

The lack of effect on most of the criteria would be due to an enormous variability and, in some cases, to the floor effect for, generally speaking, the statements were not very rich, phenomenologically.

Of the 15 criteria analyzed, however, there were two amount of detail and length that were significant for discriminating between the two types of statements and, therefore, could be of some help in distinguishing the origin of the statements. Thus, the temptation would be to use only these two criteria for an objective analysis of credibility and to discard the remaining criteria. This approach, which would mean fewer criteria, should be discarded, however, because whether these two criteria are present most likely depends on a great variety of factors, such as the type of event described, the time elapsed, and the witness's abilities, for example.

If the criteria that enable us to distinguish between true and false statements are the amount of detail and the length of the statement-the first also being especially important in evaluating a testimony as "true"-what happens with all those individuals who have limited vocabulary, semantic and autobiographical memory deficits without which they cannot satisfactorily reproduce conversations , or difficulty situating events in a given context? By the same token, many persons with ID also have great difficulty situating events in time and space Bailey et al.

Therefore, using only the two criteria shown to be significant in the study, one runs the risk of issuing an erroneous assessment of credibility-and the revictimization that would result. Discarding the 13 non-significant criteria does not seem appropriate either, however, for as the cluster analysis of all criteria shows, we would still be able to distinguish Let us remember that, in forensic psychology, the proposed maximum rate of error for a technique to be accepted as valid is 0.

Further research with these criteria, along with a system of analysis that would enable all indicators to be taken into account in making a decision, might shed more light on content-based lie detection procedures. These results, however, are contrary to those found in the previous research mentioned in the introduction, which was conducted with developmentally normal persons Manzanero, et al.

In that study, in contrast to this one, the two types of statements could be distinguished with a At any rate, this difference in the results could be accounted for by differences between the two studies in terms of not only the participants but also the events -for an actual event was used for the present study, but a filmed event and a different type of fabrication was used for the study with participants who did not have ID.

It would be advisable to conduct further research with different events and different types of fabrication so that the results could be generalized. In future research studies, testimonies given by persons with more severe ID should be analyzed on the basis of these criteria because we understand that, the more severe the disability, the more difficult it is for the individual to narrate with sufficient detail, to situate an event in a context, and to reproduce conversations.

Thus, in a population of persons with severe ID or with a specific syndrome involving language disorders, perhaps the credibility criteria that prove to be significant for distinguishing between true and false statements would be different.

Then again, the results obtained would be applicable only to those statements originating from an actual memory and to false statements generated from information about an event presented schematically. Research on persons with ID would have to be expanded to include other types of statements, such as those arising from false memories or those originating in the imagination.

In any case, false statements, regardless of their origin, are never entirely fabricated but originate, in part, from various sources of information and are developed to create something new.

In conclusion, in light of our results, we may affirm that there are complexities involved in analyzing the credibility of testimony given by an adult person with ID and, even beyond that, in designing the supportive procedures required to obtain a valid testimony.

Given the bias that may condition our intuitive credibility evaluation in persons with ID, and because such an evaluation carries a significant margin of error, it is absolutely essential that, in a law enforcement or legal setting, individuals who specialize in ID would be on hand when the testimony of a person with ID is to be evaluated. By the same token, prior to evaluating the testimony, the individual must be evaluated with regard to those abilities that could impact each of the credibility criteria used to distinguish between true and fabricated statements in this population.

Bailey, Jr. Research on fragile X syndrome and autism: implications for the study of genes, environments and developmental language disorders. Warren Eds. Bekerian, D. The truth in content analyses of a child's testimony. Bliesener Eds. International Perspectives pp. Berlin: W de Gruyter. Bensi, L. Discerning truth from deception: The sincere witness profile. Bottoms, B. Juror's perceptions of adolescent sexual assault victims who have intellectual disabilities. Law and Human Behavior, 27, Buja A.

Data Visualization with Multidimensional Scaling. Journal of Computational and Graphical Statistics, 17 2 ,

AMS-H-6875 PDF

Máster en Evaluación psicológico-forense y penitenciaria

Psychological assessment in the forensic field: early release in the Uruguayan context. Uruguay, bonillan vera. Natalia Bonilla Armada. Ministerio del Interior, Montevideo, Uruguay.


Live Webinars




Related Articles