The Panel’s composition
Fourteen senior international specialists across eight countries: neonatologists, paediatric pathologists, perinatal epidemiologists, clinical pharmacologists, ventilation-and-respiratory-physiology researchers. The specialisation mix is deliberate: a case-by-case review of a neonatal-cluster casebook needs the full range of specialist perspectives, not just general neonatology.
See our full Panel list for institutional affiliations. See evidence: Panel consensus for why the breadth matters.
Step 1: documentary preparation
For each indicted case, the Panel received: the clinical record from admission through death or survival; the post-mortem report where a post-mortem was performed; the contemporaneous clinical notes from the unit; the Crown’s trial-expert reports on the case; the defence-expert reports where available. The Panel worked from the documentary record, not from the Crown’s narrative framing of it.
Step 2: blinded case assignment
Individual Panel members reviewed specific cases without automatic knowledge of how other members were reading the same cases. This is the blinded-review standard in modern multidisciplinary clinical review. The aim is to prevent Panel-level groupthink: each specialist should bring their own independent reading.
Step 3: differential-diagnosis review
On each case, the Panel applied structured differential-diagnosis methodology:
- What natural causes could explain the observed deterioration and/or death?
- What clinical-context factors (prematurity, outbreak, staffing, infrastructure, acuity mismatch) could have contributed?
- What specific evidence, if any, would be required to support a non-natural cause?
- Is that specific evidence present in the documentary record?
- If not, what is the most likely natural-cause explanation on the available evidence?
Step 4: cross-specialist collation
After individual review, cases were collated across specialists. Where different specialists reached different readings, the differences were resolved through discussion. Where consensus could not be reached, that was explicitly noted. The Panel’s headline finding — no medical evidence of deliberate harm in any case reviewed — reflects specialist consensus, not a dissent-suppressed majority position.
Step 5: the final report
The February 2025 summary report set out the Panel’s conclusions at a headline level. The June 2025 Additional 10 Cases Report extended the review. The Joint Expert Witness Insulin Report provided specialised analysis on Babies F and L. Together they constitute the Panel’s full output.
Why this methodology is the standard
The Panel methodology is what modern UK expert-instruction standards require in serious-harm cases. Each feature — blinded review, structured differential diagnosis, multi-specialist consensus, explicit recording of uncertainty — is codified in Royal College guidance, in CPS expert-instruction protocols, and in the academic literature on expert evidence in criminal trials.
The Crown’s expert methodology at trial (Dr Dewi Evans) did not use this framework. Dr Evans worked from a suspect-first hypothesis. His review was not blinded. His differential-diagnosis was not systematic. The contrast between his methodology and the Panel’s is not a matter of specialist taste; it is a matter of which methodology meets modern standards.
What the Panel does not claim
The Panel does not claim to prove Letby’s innocence. It claims that the medical evidence in the casebook does not support a finding of deliberate harm. On the criminal-law standard of beyond reasonable doubt, a conviction that rests on medical evidence the Panel’s methodology finds unsupportive cannot be safely sustained. This is the operational form of the Cannings principle.