Psychiatrist or Psychologist? Who to instruct?

Many find it confusing to know the differences between a psychiatrist and a psychologist and which one to instruct as an expert witness. Here we seek to explain the differences and offer some examples of cases that would require one or the other.

A psychiatrist is qualified to assess both the mental and physical aspects of psychological problems. Having a medical degree alongside advanced qualifications and specialty in psychiatry.  They use talk therapy, medications, and other treatments to treat mental health conditions. Of over 200 mental illnesses, psychiatrists are able to distinguish their particular manifestations and provide the necessary medical care to support the health and wellbeing of their patients. Dealing with vulnerable individuals, the profound knowledge and clinical experience of a psychiatrist expert witness can be essential for fair trial. For example, if an incorrect diagnosis has been given, or missed entirely, it can be extremely detrimental to a solicitor’s client going into court proceedings since the court cannot make an informed judgement. If necessary, the psychiatry expert witness can assess the individual’s ability to understand and participate in the court proceedings and may be required to produce a Litigation Capacity report as a result. In a criminal defence case, the psychiatrist can give their expert medical opinion with regards to the necessary medical care of the accused. This can include giving their opinion on where the defendant should carry out their sentence – in a conventional prison or psychiatric hospital for instance.

A psychologist has an advanced degree such as a PhD or PsyD. Most commonly they use talk therapy to treat mental health conditions. They may also act as consultants alongside other healthcare providers or provide therapy for entire treatments. A psychologist expert witness can be appointed in a vast range of cases. For example, in a criminal defence case, an in-depth psychological assessment may enable the psychologist expert witness to understand what motivated the criminal activity and whether the defendant’s actions were as a result of a mental health or behavioural problem, rather than with the intent to cause harm. In a divorce case, the appointed psychologist expert witness may be required to assess the parents to determine their suitability to provide the necessary care for the children. In personal injury cases, psychologists assess a broad range of severe and catastrophic harm to the individual. They will not only differentiate between traumatic events and complex or developmental trauma, but also consider the social and family factors which may contribute to the severity of symptoms. This holistic view makes psychologists well-placed to diagnose the repercussions of a traumatic incident and offer a comprehensive overview of predictable outcomes. Conversely, psychiatry is better able to recommend and assess the effectiveness of medical interventions.

There are times when instructions will require both professions to report. For instance, if a solicitor asks for a cognitive assessment as well as an opinion on their client’s Fitness to Plead. Psychiatrists are not trained to undertake psychometric assessments so a psychologist would need to undertake this first so that the psychiatrist can use it to inform their Fitness to Plead assessment. Fitness to Plead assessments are required to be performed by professionals that are approved under section 12(2) of the Mental Health Act 1983 which does not usually include psychologists. It is often helpful to have the additional report and view of another professional from a different mental health discipline (e.g., psychiatry) but it is rarely essential, unless specific issues are raised that dictate it e.g., a medication review.

Both clinical psychology and psychiatry are sciences, using evidence-based research to evaluate the effectiveness of interventions. An important and usually misunderstood fact is that both professions diagnose mental health problems by engaging scientific, evidence-based assessment tools. But psychologists can also use ‘formulation’ to establish the cause and factors influencing mental health problems, rather than classifying people by disorders.

Psychiatrists often have a more stringent and scientific reporting style. This clear and concise presentation is often viewed as useful for the Courts. Psychology, on the other hand, spans the gap between social and biological sciences. Psychologists report on the multiple factors influencing mental health problems, basing their understanding of the disorder on childhood experiences and family influences. Consequently, their reporting style can be lengthier and cover more areas that affect the individual’s difficulties. Psychologists often recommend mixed-model interventions, responding to multiple presenting problems which can deliver beyond pure therapy or medication treatment options.

Within their individual disciplines, psychiatrists and psychologists will have a particular focus in their clinical careers. It is crucial that when an expert witness is chosen their expertise is relevant to the case. For example, a case involving minors will require a child psychologist expert witness rather than an adult psychologist who is a substance abuse specialist. If the knowledge and experience of the expert witness is not deemed relevant enough you risk their conclusions being challenged or dismissed.