Prosecution insulin expert was under formal investigation during the trial

The Guardian reveals that Prof. Peter Hindmarsh — who provided crucial evidence for the prosecution's case that Letby attempted to murder Babies F and L with insulin — was, in the period leading up to the trial, subject to a formal investigation led by his main employer UCLH, with Great Ormond Street involvement, into multiple serious concerns including allegations that he harmed patients. Expert witnesses must disclose anything capable of undermining their credibility or impartiality; Cheshire Police confirmed Hindmarsh did not disclose the investigation to the force, and the CPS said it was unaware of it before his first appearance as a witness on 25 November 2022.