Forensic, Smarter Interviewing: A Practical Look at Assessing Reliability and Truthfulness in Civil Litigation

Issues of assessing reliability and truthfulness are discussed in the context of forensic, judicial and clinical settings in relation to civil compensation cases. Theoretical and practical issues are described. The overall importance of congruent communications is stressed.

and extent of the available data (e.g., self-report, medical records), the inferences made, the precision of tests or questionnaires used, and the range of opinion. However, the most crucial data is that of the claimant's self-report, obtained from the interview. This informs the key medico-legal answers of diagnosis, causation, duration and prognosis. For the expert's opinion to be robust, fair and just, he/she must be aware of how reliable the self-report information is. These issues are discussed below in relation to an anonymised case study.

Case Study
Mr Jones (31) lives in Exeter and works in the local council offices. He drives 10 miles each way to get to and from work.
He described having a significant RTC on the M5 where it meets the A38 Devon road. He stated that he was hit from behind and pushed into the central reservation, hitting another car. He has reported that he has developed traumatic stress, a fear of driving and subsequently had to have 6 months off work and is still off, due to both physical and psychological difficulties following the RTC.

Anonymised Interview
Mr Jones walks into the clinic room, holding his back and making grunting noises -he walks slightly stooped. Q17: Did you lose consciousness when you were hit? A17: I think so, it was a real shock -I tried to avoid the barrier and the other cars and I was really relieved to come to a halt. I was worried I had been hurt but also worried because the other driver looked very shaken up.
Q18: When it was happening did you think you were going to die?
A18: Oh yes, after I got out, a policeman said I was lucky to get out alive. I think I had PTSD (no emotion shown here or when answering questions about details of the RTC).
Q19: Did you go to hospital straight away? A19: No, the next day, or maybe two days later -RD&E hospital in Exeter. Q20: Did you see your GP? Did anyone support you go? A20: Sorry, I'm not sure. Yes about one week later I think -not sure. Yes, my sister supported this would be a good idea. Q21: Did you discuss any emotional problems with your GP? Did he suggest any treatment? A21: Oh yes, we talked about it -I got given some tablets. I wasn't there long, he's always very busy. I do remember him saying he had a road accident on the same stretch of road. My sister, who is a psychologist, recommended I should have therapy or counselling. Q26: I notice that the medical report by Dr Bloggs says you said you were off work for two weeks? A26: I was, but when I went back, after two hours I couldn't cope and had another two weeks off.
Q27: Did they give you a courtesy car? A27: Oh yes, it was a big car though -I didn't drive it much. I remember saying to the garage guy that the car was much bigger than mine.
He said it was the only one available.
Q28: When you went back to work, how did you get there?
A28: A friend picked me up for the first two weeks. I was very anxious and kept pointing this out to him which made him angry. I then got my insurance money and bought another car and drove to work.  Verbal and non-verbal behaviour in the context of deception detection has been well researched [4]. Below are examples of these deception-related behaviours which were apparent in the case study (Table 1).
When assessing veracity, the interviewer looks for positive characteristics which endorse reliability. Examples of these from the case study are in table 2.
In addition to actual verbal and non-verbal characteristics of unreliability in the interview, the interviewer also listens out for general psychological characteristics, motivational factors and inconsistencies. Examples of these from the case study are in table 3.

Truthfulness Continuum: Truthfulness like most other behaviours is a continuum as shown below:
Telling the truth validly Selective truthfulness and lying and reliably On this continuum claimants commonly display the following characteristics:-

• Omission of key information
• Exaggeration of information • Inconsistency of approach between two or more areas

• Suggestibility for producing erroneous accounts under interviewing
The search for evidential certainty relies on incremental observation and consideration throughout the litigation 'trail' , the search for 'best fit' opinion, increasing objectivity and the expert's impartiality and independence.

Three Continua of Unreliability
Careful consideration of interview verbal and non-verbal behaviour results in an opinion of three linked aspects of untruthfulness: unreliability, defensiveness and malingering. The anchor points for each of these continuum is illustrated below:

Continuum of Reliable -Limited Reliability -Without Reliability
Self-report with limited reliability: The patient answers most inquiries with a fair degree of accuracy, but volunteers little or nothing and may distort or evade on circumscribed topics.
Self-report without reliability: The patient, through guardedness, exaggeration, or denial of symptoms, convinces the clinician that his or her responses are inaccurate. Such cases may be suspected of malingering or defensiveness, although the patient's intent cannot be unequivocally established.

Continuum of Not Defensive -Mild Defensiveness -Moderate Defensiveness -Severe Defensiveness
• Mild defensiveness: There is unequivocal evidence that the patient is attempting to minimize the severity but not the presence of his    or her psychological problems. These distortions are minimal in degree and of secondary importance in establishing a differential diagnosis.
• Moderate defensiveness: The patient minimizes or denies substantial psychological impairment. This defensiveness may be limited to either a few critical symptoms (e.g., paedophilic interest) or represent lesser distortions across an array of symptomatology.
• Severe defensiveness: The patient denies the existence of any psychological problems or symptoms. This categorical denial includes common foibles and minor emotional difficulties that most healthy individuals have experienced and would acknowledge.

Malingering
Continuum of Truthful -Mild Malingering -Moderate Malingering -Severe Malingering • Mild malingering: There is unequivocal evidence that the patient is attempting to malinger, primarily through exaggeration. The degree of distortion is minimal and plays only a minor role in differential diagnosis.
• Moderate malingering: The patient, either through exaggeration or fabrication, attempts to present him-or herself as considerably more disturbed than this is the case. These distortions may be limited to either a few critical symptoms (e.g., the fabrication of hallucinations) or represent an array of lesser distortions.
• Severe, malingering: The patient is extreme in his or her fabrication of symptoms to the point that the presentation is fantastic or preposterous.
Evidential certainty of deception is rarely black and white [5], but falls somewhere on the overall dimension in figure 2 below: A description of the anchor points illustrated above are shown in table 4 opposite.
The key to deception detection is the ability to listen and 'watch' interviewee's verbal and non-verbal behaviour very carefully. However, in addition to this, researchers [6] have developed a strategy for increasing cognitive load with the aim of eliciting a higher rate of deception cues from untruthful claimants. It is suggested that to do this requires: • Asking questions to raise cognitive load in liars • Making interview more difficult (reverse order story telling; keep eye contact and tell story; ask unanticipated questions; ask devil-advocate questions; strategic use of evidence (which client is avoiding e.g., use of car hire) This results in more non-verbal deceit cues and greater potential for detection.

Implications for Professional Practice
Much debate centres on how successful expert interviews can detect deceptive behaviour [7]. It is suggested that greater emphasis be placed by experts on actual interviewee behaviour, including verbal and non-verbal behaviour, and how the expert develops an incremental picture of the interviewee's veracity and to what extent there is a range of opinion when faced with this array of data.
To catch the unreliable historian out, the expert needs: • A questioning, challenging attitude • A probing, repetitious, questioning attitude where necessary • A withholding attitude at times (i.e., non-disclosure of what is already known) • Well researched, background information prior to interview • Integrate an array of clinical findings on the issue of dissimulation.
• Strength and consistency of results across various measures

• Absence of alternative explanations
This should be a subject taught at undergraduate and postgraduate levels of both psychology and law courses and also a key topic considered as part of CPD for qualified and experienced lawyers and experts in the field.