EXPERT WITNESS MUST BE INDEPENDENT
A recent medical negligence decision has reiterated that an expert witness, instructed by a party in litigation proceedings has a duty to provide independent and objective evidence. In the UK case of EXP V Barker  EWCA Civ 63, a District Court Judge sued a neuroradiologist for an alleged failure to identify and report the presence of an aneurysm in her brain in 1999. The Plaintiff experienced an episode of visual disturbance in 1999 and underwent an MRI scan which the Defendant reported on. Dr. Barker concluded that the scan was entirely normal. The Plaintiff claimed that the Defendant was incorrect and that the MRI had in fact disclosed the presence of an aneurysm. In 2011 the Plaintiff suffered an acute parenchymal haemorrhage caused by a ruptured aneurysm. The Plaintiff was left with a range of physical and mental difficulties. The expert witness instructed by the Defendant supported the Defendant in his defence of the case. It transpired that the expert witness had previously worked and had co-authored a research paper with the Defendant. The trial judge questioned the objectivity and impartiality of the Defendant’s expert witness and decided not to place sufficient weight on the evidence given by the expert.
What is noteworthy about the case is the fact that both the Defendant and the expert witness had provided CVs to the Court, however, the close relationship between the expert and the Defendant was not clear from the CVs. The trial judge found for the Plaintiff. The matter was appealed to the Court of Appeal where the Court of Appeal agreed with the decision of the trial judge and in fact stated that if the trial judge had decided to exclude the entirety of the expert’s evidence, then the trial judge would have been entitled to do so.
This decision reflects the recent recommendations of the Law Reform Commission as stated in their Report on the Consolidation and Reform of Aspects of the Law of Evidence. This Report which was published on the 18th January 2017 states that an expert has an overriding duty to provide truthful and impartial evidence. In addition the Report makes recommendations providing that four main duties of an expert witness be set out in legislation. These duties are as follows:
1. An overriding duty to the court to provide truthful, independent and impartial expert evidence;
2. A duty to state the facts and assumptions (and, where relevant, any underlying scientific methodology) on which his / her evidence is based and to fully inform himself or herself of any fact that could detract from his / her evidence;
3. A duty to confine his / her evidence to matters within the scope of his / her expertise; and
4. A duty to his / her instructing party to act with due care, skill and diligence, including a duty to take reasonable care in drafting any written report
When instructing an expert witness, it is crucial to determine whether a professional or personal relationship exists between the expert and any of the parties involved in the litigation, which may affect the independence of the expert. If such a relationship exists, then that expert should disclose this when initially instructed.