Acting as a professional or expert witness
The duty to act within one’s expertise extends beyond the remit of day-to-day clinical practice and is equally applicable to writing reports and giving evidence in court. As in clinical practice, when giving an opinion in these circumstances, doctors should ensure that they confine themselves to matters within their expertise and that they are prepared to justify their opinion and support it with evidence if called upon to do so. Before accepting instructions to act as an expert, doctors should ensure that they have the appropriate skills and knowledge to fulfil the requirements of the proposed brief.
Dr Ho, a family physician, is approached by solicitors acting on behalf of relatives of Madam Ng, a former patient with progressive vascular dementia, who recently died. There is a dispute over Madam Ng’s will and Dr Ho is asked to write a report about her testamentary capacity. He provides the report, stating that in his opinion Madam Ng had capacity at the time she made her will.
He is called to give evidence in court, where it becomes evident that Dr Ho did not make a formal assessment of Madam Ng’s capacity when he wrote the report, nor can he recall the elements of the tests he should have applied when assessing testamentary capacity. Dr Ho’s credibility is called into question and, as a result, the relatives’ claim fails. They complain to the Medical Council, who reprimand Dr Ho for acting outside his expertise.
Acting outside one’s own experience and knowledge, even with the best of intentions, is rarely in the patient’s best interests
Finally, one of the basic tenets of medical ethics is primum non nocere (first do no harm), another element of the Hippocratic Oath. Acting outside one’s own experience and knowledge, even with the best of intentions, is rarely in the patient’s best interests. Doctors should know their limitations and, when faced with matters beyond their personal expertise, refer patients to those with the appropriate knowledge and skills. In an emergency or where the patient refuses specialist referral, the doctor should do the best he can for the patient within the limitations of his capability.