Medico-Legal Implications of Assessing Unreliability in Civil Compensation Cases: A Case Study Reflecting Potential Unreliability
The expert witness assessing claimant self-report behaviour in the interview needs to be able to identify characteristics reflecting reliability and/or unreliability. This case study uses interview data to illustrate key aspects of veracity and its implications for therapeutic jurisprudence. Conclusions about using a checklist for unreliability are made.
Keywords: Reliability; Truthfulness; Non-verbal Behaviour; Work Accident; Logicality
When collecting evidence in a civil claim for personal injury such as a work accident, the expert witness (of any clinical/medical speciality) must be mindful of the reliability of data and truthfulness of the claimant.
The importance of maintaining a ‘moral compass’ between various conflicts or inconsistencies of data is a complex task undertaken by lawyers and experts, working together with independence, impartiality and logicality  and reflects an increasingly ‘therapeutic’ or ‘continuous improvement’ approach to contemporary 21st century litigation .
From a legal perspective, evidential reliability is based on the quality and extent of the available data, inferences made, precision and validity of test results-however, the central data is that of the claimant’s self-report, obtained from a face-to-face interview. From this, key medico-legal questions of causation, attribution, diagnosis, duration and prognosis can be answered. Recent Legal Mind cases and commentaries [3-6] have illustrated this. Within the interview assessing psychological injury, there are many areas of potential unreliability [7,8] both clinical and medico-legal. Many of these are explored via the interview and a series of verbal, non-verbal and procedural indicators aid the expert in his/her assessment of reliability .
The key to assessing malingering and deception in forensic, judicial and clinical contents is to ascertain the extent to which communications are congruent . The expert uses a semi-instructed interview to ‘listen’ for descriptions of symptoms which may appear unsound or unreliable . Examples of possible unreliable communications such as non-verbal behaviour (e.g. speech hesitation), verbal behaviour (e.g. level of detail, superficiality) and general characteristics (e.g. inappropriate language, suggestibility, inconsistency) have been illustrated with reference to actual interview data  These must, however, be considered in the context of interviewing to detect deception still being a very difficult area of inquiry with general detection rates being problematic. An anonymised case study in shown below.
Mrs. Smith (43) lives in London and works as a hospital cleaner. Whilst at work she slipped on a wet hospital floor, injured her back and her left leg and hit her head. She was off work for six months. She reported that she became depressed while off work and also developed social anxiety about being out of home and walking on non-dry surfaces.
The following summary (Figure 1) of statements made in her interview with a clinical psychologist/expert witness is shown below with relevant unreliability characteristics of potential unreliability alongside to highlight the expert’s reaction to what he was being told.
In Figure 2 below examples of statements are given which can indicate general characteristics of reliability and truthfulness which can be balanced against other indications of un-reliability. The expert interviewer must be mindful not to place too much emphasis on any one facet of behaviour.
Having considered the actual verbal and non-verbal behaviour of the claimant in the face-to-face interview, the expert then assesses a number of psychological characteristics which can reveal underlying unreliability (Figure 3).
The expert witness has the unenviable task of collating not only basic self-report and medical record information but also the large number of characteristics of potential reliability or unreliability . As yet, there is no systematic or scientific way of doing this. However the use of the several deception detection variables illustrated in the case study statements in Figures. 1-3 are an important basis on which to identify, collect and debate levels of reliability and truthfulness in claimants. Further work is underway to develop a scientific way to more formally operationalise this data on three overlapping dimensions of reliability, defensiveness and malingering – this case study method is an invaluable tool to support and progress this process and hence be able to advise the court on veracity and evidential certainty. Recent work  on developing a tool to increase the validity of judgements of credibility in medico-legal settings is being investigated and will be the subject of further research and publications . This analysis is important for lawyers and experts, qualified and in training to be aware of. Alongside this type of analysis, credibility assessment is also aided by serial interviews, interviews with ‘significant others’, understanding effects of poor memory on recall and being aware of the differential effects of anxiety on behaviour and responding. The final question which the proverbial ‘Judge’ will ask (“Dr. Expert, putting all this information and inference together, how reliable or truthful is Mr. X?”) is still an extremely difficult one to answer logically and reliably. However, this work on identifying and attempting to interpret in a balanced and logical way the extent of unreliability or untruthfulness is crucial in forensic, judicial and clinical contexts. 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 experts in the field.