9. Is the opinion of the single joint expert always accepted by the court?

9. Is the opinion of the single joint expert always accepted by the court? 

No. The opinion of a Single Joint Expert (“SJE”) is not binding on the court. Although an SJE’s report is typically assigned substantial weight, the court remains the ultimate tribunal of fact and retains sole authority to evaluate expert evidence in light of the entire body of evidence. 

An expert witness, including an SJE, is instructed to assist the court on matters within his expertise, overriding any obligation to the instructing parties. However, the court is not bound to accept the SJE’s conclusions, particularly if the opinion is unsupported by sound reasoning or authority. 

Where the SJE’s evidence deals with non-factual opinion matters (such as asset valuation or technical assessment) and stands uncontradicted by other direct evidence, it is highly compelling. In such cases, the court will depart from the SJE's conclusions only in exceptional circumstances and for cogent, fully explained reasons. 

Where an SJE’s opinion conflicts with credible direct factual evidence given by lay witnesses (e.g., eyewitness testimony regarding accident circumstances), there is no rule of law requiring the judge to favour the expert over the witness of fact. The judge must attempt to reconcile the conflict and, if impossible, make a considered choice based on the totality of the circumstances. 

The appointment of an SJE does not permanently bar a party from seeking contrary expert evidence. However, parties cannot automatically call their own experts to refute an SJE. Court leave is strictly required to set aside or vary the SJE order pursuant to Order 38, rule 4A(7) or rule 44 of the RHC or RDC. The court may allow the parties to do so if the party’s dissatisfaction with the SJE report was not “fanciful”.