Why it matters in the Letby case
Independent critique has examined how the prosecution expert evidence in the Letby case maps to these duties.
Legal explainer
Expert-evidence duties in criminal cases
Under Criminal Procedure Rules Part 19, experts owe their primary duty to the court — not to the party instructing them. Reports must state the scope of inquiry, methodology, sources relied on and limits of the conclusions reached.
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Prosecution position
The Crown called expert witnesses whose evidence was admitted at trial and tested in cross-examination.
Expert challenge / post-conviction reading
Independent critique has examined how that evidence maps to the duties in Criminal Procedure Rules Part 19 — the primary duty to the court, and the requirement to state the scope of inquiry, methodology, sources relied on and the limits of the conclusions reached. Two clinicians filed a formal GMC complaint concerning the prosecution expert evidence.
What remains uncertain
A complaint is not a finding. Whether any expert fell short of their Part 19 duties is not something this site determines, and the regulatory processes have their own thresholds and timescales.
Common questions
What duties does an expert witness owe?
Under Criminal Procedure Rules Part 19 the primary duty is to the court, not to the instructing party. Reports must state the scope of inquiry, the methodology, the sources relied on, and the limits of the conclusions.
Why does 'primary duty to the court' matter?
Because an expert is not an advocate. The rule exists to stop expert evidence being shaped by the interests of whoever instructed it.
Has a complaint been made in this case?
Yes — Dr Svilena Dimitrova and Roger Norwich co-filed a formal GMC complaint regarding the prosecution expert evidence of Dr Dewi Evans. A complaint is not a finding.
Does the site take a view on the experts?
No. It records what is on the public record about the evidence and the duties that apply to it.
Related reading
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