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1 November 2018

Why is it important to assess cognition in criminal cases?

Dr Seán Haldane is a Consultant Neuropsychologist and expert witness who provides reports for defence lawyers, the Crown Prosecution Service and the police. We caught up with Dr Haldane to discuss how CANTAB Insight is integral to his work.  

Neuropsychological assessment is vital in criminal cases in such questions as:

  1. ‘Is a person fit to plead?’ This applies to whether the accused can enter a plea of guilty or not guilty, and to such questions as whether he or she is able to instruct counsel (barristers) or object to jury members. These questions are based on the case of R v. Pritchard (1836), and are known as the ‘Pritchard rules’.
  2. ‘Is a person fit to testify?’ This applies to whether a person accused of a crime, a victim of a crime, or a witness to the crime is able to testify in court.
  3. Does an accused person considered fit to testify but who is neuropsychologically impaired require special conditions in court?  (E.g. an intermediary, or a modified style of cross examination.)
  4. Was the person accused of a crime neuropsychologically impaired when the crime was committed? If so, how did a specific impairment affect his or her behaviour at the time? Was the person capable of mens rea – Latin for ‘mind in the thing’: i.e. did they know what they were doing?
  5. Does neuropsychological impairment prevent accurate recall about or relation of information about the crime and related incidents, by the accused, the victim, or a witness?  


What is involved in creating a neuropsychology expert witness report?

Neuropsychology assessments are often vital in achieving justice in court. Almost all neuropsychology expert witness reports include psychometric testing (the exceptions being where this is impossible due to extreme impairment or medical conditions), centring upon IQ assessments. However, the determination of a person’s IQ is not in itself useful in forensic work. A person’s level of intelligence has nothing to do with responsibility in a crime, unless the person is learning disabled, and even then the person may be considered fit to plead if they satisfy the Pritchard rules.

With this in mind, I prefer to use CANTAB Insight in my psychological assessments, as I find it to be extremely useful and practical in court.


Why do you use CANTAB Insight in your expert reports?

In my practice as an expert witness, my assessment requires an interview of two or three hours, including psychometric tests in which CANTAB Insight has become the vital core. Occasionally I have had to discontinue psychometric tests because the subject becomes hopelessly muddled or distressed. I have almost never had to discontinue CANTAB Insight. Almost always the person becomes engaged in the testing and enjoys it.

CANTAB Insight is the best and most practical neuropsychology assessment I use in expert witness reports in criminal cases.


What are the advantages of assessing cognition for a court case?

I have discussed findings from Insight with prosecution and defence counsel (barristers in court), in conferences preceding court cases as each measure is of obvious relevance to cross examination:

  • Attention : Is the subject likely to pay attention?
  • Episodic Memory : Will they recall questions or information given a short time before?
  • Working Memory : Will they be able to follow court proceedings and remain engaged in them?
  • Speed of Processing : Will matters have to be taken slowly, or can they be discussed at a normal pace? 
  • Executive Function : Will the person be able to stay on the subject and decide ‘off the cuff’ on what is relevant or not – to organise their responses?

It is certainly useful for barristers, and for that matter the judge, to know roughly how intelligent the subject is, and something of his or her intellectual strengths and weaknesses, as can be determined in tests of intelligence and memory. But it is clear that Insight provides just the sort of practical information which is most useful to the court during the trial. It also provides the practical information which is necessary in legal question (3) above: does the accused or a witness need special help in court – e.g. from an intermediary?


About the author. When I left the NHS in 2013 I started a part time private practice in neuropsychology which has now become almost entirely providing expert witness reports in criminal cases. Currently about a third of my reports are for defence lawyers, and two thirds for the prosecution – the  Crown Prosecution Service (CPS) and Police. My CV is held by the National Crime Agency.


Interested in using CANTAB Insight in your expert reports?

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Tags : cantab | law | cognition | insight | neuropsychological assessment | expert witness | cantab testimonial

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Dr Seán Haldane, Consultant Neuropsychologist