Lucy Letby Trial Expert Witness Was Under GMC Investigation During Testimony
In a startling revelation, it has emerged that Professor Peter Hindmarsh, a key expert witness for the prosecution in the Lucy Letby trial, was under investigation by the General Medical Council (GMC) for fitness to practise concerns while giving evidence. The jury was never informed about this investigation, which included allegations of harm to patients, raising serious questions about the transparency of the trial proceedings.
Investigation Coincided with Trial Testimony
The GMC opened its formal investigation into Professor Hindmarsh on the very first day he testified in late 2022, and it continued during his second appearance three months later. The investigation was prompted by referrals from Great Ormond Street Hospital and University College London Hospitals Trust (UCLH), following a formal inquiry into multiple and wide-ranging concerns about his clinical practice. These concerns included allegations of harm to paediatric patients, inappropriate diagnoses, and inadequate documentation.
Despite the ongoing investigation, a medical tribunal allowed Hindmarsh to continue serving as an expert witness in the Letby trial, imposing only the condition that he inform instructing parties of the GMC probe. However, the Crown Prosecution Service (CPS) opposed informing the jury, arguing that the allegations had not reached a final adjudication. Ultimately, the investigation was never concluded because Hindmarsh removed himself from the GMC register through voluntary erasure in November 2024, avoiding any regulatory finding.
Impact on Trial and Convictions
Professor Hindmarsh's evidence was pivotal in the prosecution's case, particularly regarding allegations of insulin poisoning in two babies, which the prosecution described as "incontrovertible" evidence of deliberate harm. His testimony supported the claim that hypoglycaemia in the infants resulted from insulin injected into fluid bags, though no direct forensic evidence linked Letby to this act. The jury, unaware of the GMC investigation or the underlying concerns about Hindmarsh's practice, found Letby guilty in these insulin cases, with some verdicts being unanimous.
Since Letby's convictions for murdering seven babies and attempting to murder seven others, numerous medical experts have contested Hindmarsh's evidence. A panel led by Dr Shoo Lee concluded that the babies' collapses were due to natural causes and poor care, not murder or insulin poisoning. Letby's legal team has applied to the Criminal Cases Review Commission (CCRC) to review the case, supported by reports from 27 experts who argue the convictions are unsafe.
Disclosure and Ethical Concerns
The failure to disclose the GMC investigation to the jury has sparked ethical debates. Under criminal procedure rules, expert witnesses must disclose anything that could undermine their credibility. While Hindmarsh informed the police of the investigation in December 2022, the CPS did not disclose this to the defence until just before his second testimony. The defence did not apply to inform the jury, and the reasons remain unclear due to client confidentiality.
This case highlights potential flaws in the justice system regarding expert witness transparency. As the CCRC reviews Letby's application, the role of Hindmarsh's evidence and the undisclosed investigation will be scrutinised, with implications for future trials involving medical testimony.
