In Bruff-Murphy v Gunawardena(1) the Court of Appeal confirmed the ongoing gatekeeper function of trial judges in the context of expert testimony. A trial judge’s role does not end after the preliminary threshold stage, but continues throughout the proceeding to protect the justice system’s integrity. Inaction on the part of the trial judge can lead to unfairness in the proceeding, requiring a new trial. Trial judges are not powerless once an expert witness has begun testifying – rather, they have an ongoing duty to ensure that there is no acute risk to the trial’s fairness.
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