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Legal and Criminological Psychology (2008), 13, 299–307 q 2008 The British Psychological Society
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Interrogative suggestibility, self-esteem, and the influence of negative life-events Kim E. Drake*, Ray Bull and Julian C. W. Boon School of Psychology, University of Leicester, UK Purpose. Past research has frequently demonstrated the impact of life adversity on the behaviour and mindset of individuals. In terms of the formal police interview, the experience of negative life-events may have an effect upon interviewee performance. This study, therefore, aims to investigate how negative life-events may influence interviewee performance on the Gudjonsson suggestibility scale (GSS). Moreover, selfesteem will also be investigated in relation to both the experience of negative life-events and interrogative suggestibility. Method. Sixty participants were administered the GSS1. In between the immediate and delayed recall phases, interviewees were asked to complete the culture-free selfesteem inventory, the life-events questionnaire and the Eysenck personality questionnaire. Results. Negative life-events (NLEs) were significantly correlated with all of the GSS suggestibility scores (yield 1, yield 2, shift and total Suggestibility). Contrary to past research, however, self-esteem scores were not significantly related to any of the GSS components or to NLE scores. Conclusion. This paper is the first to show a link between the experience of NLEs and GSS scores. The findings suggest that interviewees reporting a high number of NLEs are significantly more susceptible to the leading questions, as well as to negative feedback, administered during the GSS interview. Erroneous reports and false confessions may thus be more likely with such interviewees, potentially classifying them as vulnerable witnesses.
Concern has been expressed in a number of countries regarding the possible undesirable effects in police interrogations and/or court questioning of (a) misleading or suggestive questions and (b) negative feedback (e.g. the interrogator or questioner indicating that some responses are wrong; Milne & Bull, 1999). However, while some of the police forces are trying to reduce their use of inappropriate tactics (Bull & Milne, 2004), robust questioning/interviewing may still be commonplace in many countries.
* Correspondence should be addressed to Kim Drake, School of Psychology, University of Leicester, Lancaster road, Leicester, LE1 9HN, UK (e-mail:
[email protected]). DOI:10.1348/135532507X209981
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The concept of interrogative suggestibility (IS) is centred on how people come to accept leading questions. Stern (1910, p. 273) defined leading questions as ‘those for which a particular answer is readier than others’ and demonstrated that leading questions can provoke distorted recollections, because they can be phrased in a way as to suggest an incorrect response (Stern, 1939). In terms of the formal police interview, Gudjonsson and Clarke (1986) defined IS as the ‘extent to which, within a closed social interaction, people come to accept messages communicated to them during formal questioning and as a result, their behavioural response is affected in such a way as to either accept or resist the suggestion’ (Gudjonsson, 2003, p. 345). Furthermore, Gudjonsson and Clarke distinguished two types of suggestibility: susceptibility to leading questions (yield) and susceptibility to interrogative pressure (shift). Hence, certain interviewees may be more vulnerable to leading questions whilst others more liable to the influence of negative feedback delivered by the interrogator. Gudjonsson (1984) developed a psychometric measure, the Gudjonsson suggestibility scale (GSS), in order to assess the degree of susceptibility to either leading questions or negative feedback. In other words, it was designed to measure the extent to which the interrogator is able to shift unwanted (but perhaps correct answers) by negative feedback, as well as susceptibility to leading questions (yield). Fundamentally, the purpose behind the GSS is one identifying vulnerable individuals in possible need of protection from the manipulative tactics and interrogative pressure, often incorporated within police interviews around the world. Testing IS thus entails the administration of the GSS [of which there are two parallel forms (Gudjonsson, 1984, 1997)], during which interviewees are read a narrative, tested on their immediate free-recall, given a distracter task, tested on their delayed free-recall, and then subsequently questioned. Interviewees are asked 20 questions, 15 of which are misleading. Negative feedback is then administered by the interviewer, following which the 20 questions are repeated. Accordingly, the two form of IS, proposed by Gudjonsson and Clarke (1986), can be measured: (1) susceptibility to misleading questions prior to and post-negative feedback and (2) vulnerability to negative feedback – the extent to which interviewees change their answers when they are told that they have made a number of errors. Individual differences in IS can thus be readily measured. Past research has frequently demonstrated the detrimental impact of life adversity upon the behaviour and mindset, of an individual (e.g. Essex, Klein, Cho, & Kraemer, 2003; Andrews & Wilding, 2004; Todman & Drysdale, 2004; Becker, 2006). Specifically, experiencing negative life-events on a regular basis may have an adverse affect upon an individual’s self-esteem. Furthermore, the accumulation of negative experiences may also result in negative expectations about their own performance on future tasks (i.e. having repeatedly performed poorly at interviews, the person may come to expect to perform inadequately on subsequent occasions; Thelwell, Lane, & Weston, 2007). When faced with the somewhat arduous task of having to recall an event, and subsequently face questioning (i.e. the GSS procedure), interviewees with an experience of negative life-events may be more prone towards feelings of uncertainty (with regard to the correct answers/recollections required Gudjonsson & Clarke, 1986). In order to deal with that uncertainty, and the threat of inadequate performance, inefficient coping mechanisms may be employed [e.g. the greater reliance upon the interviewer for guidance as to whether the interviewee has answered correctly (Gudjonsson, 1988; Emmett, Clifford, & Gwyer, 2003), particularly through facial cues and interviewer demeanour (Baxter & Boon, 2000; Baxter, Jackson, & Bain, 2003)]. Instances of this may occur, particularly post-negative feedback, when interviewees are
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told by the interviewer that they have ‘made a number of errors, and therefore it is necessary to go over the questions once more, and this time try to be more accurate’. Such feedback may reinforce the established negative performance expectations of those interviewees, occasioning an even greater application of ineffective coping strategies when faced with the second round of interview questions. In short, this may encourage an increased vulnerability to any misleading information delivered during the interview. Interviewees with the experience of negative life-events may also be more likely to shift their initial answers in response to the negative feedback delivered (after the first round of questions) by the interviewer, in order to avoid further critical feedback (McCall & Struthers, 1994; Kaissidis-Rodafinos & Anshel, 2000), to appear favourable to the interviewer, and to also meet the perceived expectations of the interviewer. That is, interviewees reporting a high number of life adversities may feel that the interviewer expects them to know the correct answers (Gudjonsson & Clarke, 1986). Such interviewees may show a propensity towards trying to meet those perceived expectations. Furthermore, some studies investigating self-esteem in relation to the GSS have yielded significant findings. Not only that, but negative correlations have also been found between the experience of life adversity and self-esteem (Peterson & Taylor, 1980; Cohen, Burt, & Bjork, 1987). This study will, therefore, not only investigate the influence of life adversity upon interrogative suggestibility, but also aims to explore selfesteem levels in relation to both the experience of negative life-events and performance on the GSS. Accordingly, the hypotheses investigated in this study are as follows: (1) Interviewees reporting a greater number of NLEs will obtain significantly higher yield and shift scores on the GSS, (2) interviewees with higher negative life-event scores will have lower self-esteem scores, (3) interviewees with low self-esteem scores will show elevated suggestibility scores on the GSS and (4) interviewees reporting a high number of NLEs will have significantly poorer recall of the GSS narrative and, if so, may be more easily affected by the misleading questions and the negative feedback
Method Participants The sample consisted of 60 participants, 33 female and 27 males with a mean age of 26.8 years (SD ¼ 11:32 years, range 18 to 65 years). Participants were randomly selected from a variety of occupations, including manual labour, self-employed, academics, teachers, the business sector, unemployed, university students and sixth-form pupils. None had any prior experience of interrogation procedures.
Instruments The scoring of the GSS1 (Gudjonsson, 1984, 1997) Memory recall The memory recall task is presented in the form of a narrative, split into 40 ideas. That is, the story is made up of 40 small instances, occurring in a specific order. Each instance is scored as ‘successfully recalled’ if the interviewee is able to correctly articulate that instance. The interviewee does not need to recall each instance in the order with which they are presented in the story. Furthermore, the words used (by the interviewee) to
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recall the instances need not be exactly as written in the narrative. Of fundamental importance is that the concept, that is what occurred within each instance, is correctly recalled. The maximum score to be achieved is 40, which indicates that the interviewee has correctly recounted everything that occurred in the story. Immediately upon entering the interview room, interviewees are told by the interviewer that they are going to be read a story and to ‘listen carefully because I am going to ask you to tell me everything you can remember about the story’. The interviewee is then read the story. Upon finishing the story, the interviewee is asked ‘I would now like you to tell me everything that you can remember about that story’. Directly thereafter, a distracter phase is undertaken. In this study, three questionnaires are completed by the interviewee. On completion of the questionnaires, the interviewee is asked ‘I’d like you to tell me once again what you can remember about the story’, and their delayed-recall of the narrative is then examined. Suggestibility Following the recall-phase of the GSS, the interview-phase commences. The interviewee is asked 20 questions about the story, 15 of which are misleading. That is, they contain information that was either not in the story or information that is in some respect false or misleading. The idea is to see how easily interviewees accept the misleading information in those questions (i.e. how suggestible an interviewee is). The first round of 20 questions comprises the yield 1 scale, indicating the number of misleading questions yielded prior to negative feedback. Immediately after the first round of questions, negative feedback is given by the interviewer. The interviewee is told ‘you have made a number of errors, and it is therefore necessary to go through all of the questions once more and this time try to be more accurate’. All 20 questions are then repeated, in order to see how readily the interviewee shifts their initial answers (e.g. from ‘yes’ to ‘no’) in response to the questions asked. A yield 2 score is also obtained, depicting the number of misleading questions yielded to post-negative feedback. The scale provides four scores: (1)
(2) (3)
(4)
Yield 1. For each of the leading questions that are answered in the affirmative the first time round or in the case of false alternative questions where one of the alternatives is chosen, one Yield point is obtained. Thus, the range of possible Yield 1 scores is from 0 to 15. Yield 2. This is scored in an identical manner to Yield 1, following administration of the negative feedback. Once again, the range is from 0 to 15. Shift. Changes in response to any of the 20 questions, after their administration the second time, contribute to the ‘shift’ score. Thus, the ‘shift’ score can range from 0 to 20. Total Suggestibility. This is calculated by summation of Yield 1 and Shift scores. The maximum score is therefore 35.
Life-events questionnaire (LEQ) (Norbeck, 1984) The LEQ, containing 82 items, is a modification of the instrument developed by Sarason, Johnson, and Siegel (1978) and consists of the addition of nine items of particular relevance to women, such as ‘Major difficulties with birth control pills or devices’, ‘Custody battles with former spouse or partner’ and ‘Being a victim of a violent rape or assault’. Furthermore, the items in the LEQ were modified to reduce gender bias.
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Participants were required to go through all the events listed, and if they had experienced them at any point of their life, to circle whether it had been a ‘good’ experience or ‘bad’ experience. Following that, participants were instructed to rate the extent to which those events had an affect on their lives at the time. The ratings went for 0 to 3, 0 being ‘no affect’ and 3 being ‘large affect’. The negative life-event scores are obtained from the summation of the impact ratings for all items designated as ‘bad’ by the respondent. The questionnaire was originally designed to examine life-events experienced over the past year. However, research has shown the importance of studying life-events during adolescence, as this period is characterized by many physical, social and cognitive changes (Cohen, Burt, & Bjorck, 1987). Therefore, in order to assess the relationship between life-events and IS, examining events spanning the entire life of the individual was deemed more appropriate. As a result, participants were given the instruction to ‘read through the events listed, and mark the ones that have occurred throughout your whole life, not just past year’. Culture-free self-esteem inventory (CFSEI, adult version) (Battle, 1981) The CFSEI has been shown to be a valid and reliable way of measuring self-esteem amongst adult populations. It comprises 40 items divided into the following subscales: general self-esteem (GSE, 16 items), social self-esteem (SSE, 8 items), personal selfesteem (PSE, 8 items) and lie-scale items (8 items). The lie-scale serves to indicate defensiveness. The inventory therefore consists of 32 items intended to measure an individual’s general, social and personal self-esteem which, altogether, makes up the total self-esteem subscale. Participants are instructed to tick either ‘yes’ or ‘no’ in answer to all 40 items (i.e. the self-esteem items and the lie-scale items). A total self-esteem (TSE) score is derived through the summation of each of the three self-esteem subscale scores. It is this total self-esteem score that will be used in this study. The alpha-coefficients range from 0.57 for SSE to 0.78 for GSE. The test–retest reliability for TSE is 0.81. Eysenck personality questionnaire (EPQ) (Eysenck & Eysenck, 1975) The EPQ consists of 90 items with dichotomous response choices, split into four subscales: Extraversion (E: 21 items), Neuroticism (N: 23 items), Psychoticism (P: 25 items) and a Lie-scale indicative of social desirability (L: 21). Scores for each dimension are calculated by summing the ‘Yes’ responses. All of the four subscales have satisfactory reliability coefficients for normal adults; the N scale has a test–retest reliability of 0.86. Excellent internal consistency is also reported for the N scale, with Cronbach’s alpha values of 0.84 for men and 0.86 for women. The EPQ was, however, only included in this study in order to ensure an adequate time interval between the immediate and delayed recall phases of the GSS.
Procedure The participants were recruited for the purpose of a decision-making study, containing firstly a memory test, and followed by a decision-making exercise. A final year honours student, who had been given instruction in the use and administration of the GSS1 by a qualified forensic psychologist, administered all tests individually.
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The administration of the GSS1 employed the guidelines recommended by Gudjonsson (1984) (the procedure for this is described above). In addition, the CFSEI, LEQ and EPQ were completed between the immediate and delayed recall phases of the GSS. Following the completion of the procedure, participants were thanked for their assistance and asked not to discuss the procedure. A full debriefing was given to the participants after the data collection phase. Data analysis was completed using SPSS version 12. Correlations were used to investigate the relationships between negative life-event scores, self-esteem scores and GSS scores.
Results Mean scores Table 1 shows the mean and standard deviation scores for all the tests. Table 1. Mean (M) and standard deviation (SD) scores on the GSS1, LEQ and CFSEI for adults (N ¼ 60)
GSS1 Immediate recall Delayed recall Yield 1 Yield 2 Shift Total suggestibility LEQ Negative life-events CFSEI Total self-esteem
M
SD
14.4 13.1 5.78 8.10 5.38 11.2
5.76 5.80 2.73 3.22 2.75 3.79
21.2 23.8
12.5 5.43
Correlational data Principally, the aim was to examine the relationship between scores of NLEs and the GSS components. As predicted, the correlations between NLEs and all of the GSS-suggestibility components (yield 1, yield 2, shift and total suggestibility scores) were statistically significant; r ¼ :489; p , :001, r ¼ :546; p , :001 and r ¼ :682; p , :001, respectively. In order to examine the possibility that NLEs may be negatively related to immediate recall of the items within the GSS narrative, correlations between NLE scores and both (a) the total number of items recollections and (b) accuracy of recollection (Koriat & Goldsmith, 1994, 1996) were performed. In order to calculate an output-bound measure of accuracy for each participant, the total number of items reported correctly was divided by the number of items each reported (i.e. the original GSS immediate recall score). The correlations between NLEs and immediate memory (in terms of total number of statements recollected as well as accuracy of such reporting) were very low and not significant; r ¼ :003; p . :05, and r ¼ 2:078; p . :05, ruling out memory performance as an explanation of the above correlations between NLEs and suggestibility.
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A subsidiary objective was to explore self-esteem scores, measured using the total self-esteem scores of the CFSEI, in relation to both NLE and GSS scores. Contrary to some past research, the correlations between self-esteem and GSS scores (yield 1, yield 2, shift and total suggestibility) were not statistically significant; r ¼ 2:103; p . :05, r ¼ 2:084; p . :05, r ¼ 2:202; p . :05, r ¼ 2:199; p . :05, respectively. In addition, NLE and self-esteem were also not significantly related; r ¼ 2:228; p . :05. Thus, structural equation modelling was not necessary.
Discussion The primary aim of this study was to investigate the link between the experience of negative life-events and interrogative suggestibility. It was hypothesized that interviewees reporting a high number of life adversities may be more susceptible to the certain tactics used by the interviewer (that is the misleading questions and the negative feedback) bringing about heightened suggestibility scores. The results obtained support the first hypothesis, with interviewees reporting a greater number of negative life-events producing significantly higher scores across all of the suggestibility components of the GSS (yield 1, yield 2, shift and total suggestibility). That such interviewees yield to misleading questions more readily post-negative feedback lends support to the proposition that these elevated GSS scores may reflect an underlying negative performance expectation on the part of the interviewee. As suggested, the critical feedback may reinforce interviewees’ negative performance expectations, contributing towards an even greater acceptance of the misleading information (yield 2 scores) post-negative feedback when compared with the number of leading questions yielded to prior to the negative feedback (yield 1 scores; Gudjonsson & Clarke, 1986). In addition, the elevated shift scores obtained for interviewees reporting high scores of negative life-events is a possible indicator of such interviewees wanting to appear favourable to the interviewer (Singh & Gudjonsson, 1984; Baxter, Jackson, & Bain, 2003), to meet the interviewer’s expectations of success, and increased uncertainty levels (Gudjonsson & Clarke, 1986). Overall, interviewees scoring high on negative life-events may expect to perform with greater inadequacy (even if in reality that is not the case), predisposing them towards the application of ineffective coping strategies in order to cope with their uncertainty as to the correct answers to the incoming GSS interview questions (Gudjonsson, 1988). Rather than admitting their uncertainty or adhering to their own recollections of the GSS narrative, such interviewees may readily accept the information delivered in the interview-questions, believing that that information is more likely to be correct. This belief combined with (a) the perception that the interviewer expects the interviewee to know the correct answer(s) and (b) a greater degree of uncertainty, may contribute towards the heightened suggestibility levels observed in interviewees reporting a high number of negative life-events. There may be though some further limitations to this study, the first being problems with regard to self-reporting NLEs, e.g., under and/or over-stating NLEs, are possible problems associated with assessing NLEs using the LEQ. In addition to this, the relatively small sample may mean that the present findings may not necessarily be transferable on to the population. (However, the correlations were relatively large). In contrast to some past research (e.g. Singh & Gudjonsson, 1984; Gudjonsson & Lister, 1984), self-esteem scores were not significantly correlated with negative life-events or the GSS. The latter result was particularly surprising considering
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the abundance of literature reporting a link between self-esteem and interrogative suggestibility. With regard to the CFSEI, it is possible that interviewees may have overemphasized their positive attributes and conversely may have downplayed the negative, affecting the accuracy of the self-esteem scores obtained and obscuring the previously demonstrated significant relationship between self-esteem and performance on the GSS. In conclusion, the experience of negative life-events has been found to impact considerably upon interviewee susceptibility to misleading information and negative feedback incorporated within an interview. Both of these aspects have important implications for the practice of police interrogations, in that interviewees with a high number of negative life-events may more easily accept any misleading information put forward to them, as well as be more prone to shifting their initial answers in response to interrogative pressure. What these findings suggest is that the experience of life adversity may make interviewees more vulnerable to the vigorous police interview techniques that are still somewhat prevalent in many countries around the world. This, in-turn, may have a serious knock-on effect on the accuracy of the evidence obtained from such interviewees. Furthermore, false confessions may also be more likely as a result (Memon et al., 2003; Kassin & Gudjonsson, 2004). Such interviewees could therefore be considered vulnerable witnesses, in need of protection from the coercive tactics often employed.
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