What haemophilia carrier status means
Haemophilia is an X-linked bleeding disorder caused by deficient or defective clotting factor VIII (haemophilia A) or IX (haemophilia B). Female carriers of the haemophilia gene can have clinically relevant factor deficiency themselves, with bleeding- susceptibility that exceeds that of the general population. In male carriers — a rarer genetic situation — the deficiency is typically full.
A neonate with documented haemophilia carrier status has an elevated risk of bleeding events, bleeding-related circulatory instability, and bleeding-related collapses. This is not a hypothetical risk; it is the documented natural history of the condition.
The prosecution theory
The Crown alleged Lucy Letby had caused Baby N’s deterioration by airway interference or injection, producing bleeding from the mouth and circulatory instability. The count was one of two counts on Baby N; the jury failed to reach a verdict on both.
What independent specialists read
- Haemophilia carrier status fully accounts for bleeding. A documented bleeding disorder is, in any clinical differential, the first explanation for bleeding and bleeding-related collapse. The Crown’s theory required an external cause for bleeding the patient’s own genetics already supplied a cause for.
- Clotting-factor testing should have been the starting point. A blinded differential-diagnosis review of a haemophilia-carrier infant with bleeding would begin with a clotting-factor assay. The trial record does not show this differential being systematically pursued.
- Airway-interference hypothesis not positively established. No contemporaneous finding supported deliberate airway interference. The inference ran backward from bleeding-and-collapse to alleged airway act.
- The jury’s non-verdict is evidentially significant. The jury did not convict on Baby N. The fact that it could not reach a verdict on the haemophilia carrier’s case, while convicting on other counts, suggests the pattern-evidence argument is less compelling when applied to a baby with a documented alternative explanation for her presentation.
Why the non-verdict matters
The Crown’s case relied on a pattern argument: one nurse, many babies, many deteriorations. If the pattern argument is correct, each individual count should persuade the jury. The jury’s inability to agree on Baby N, on Baby J, on Baby Q, and on one Baby H count suggests the pattern did not carry even in the original jury’s consideration.
Independent specialist review of the non-verdict cases is not a re-litigation of what the jury decided; it is a reading of why those specific cases did not meet the pattern’s own logic. Each of the non-verdict cases has an identifiable natural- pathology alternative that the jury appears to have found sufficient to refuse conviction.
What the Panel says
The Panel’s case-by-case review of Baby N reads the presentation as consistent with symptoms arising from the underlying bleeding disorder. This is not a claim that Letby acted innocently in Baby N’s specific case; it is a claim that the Crown’s theory does not explain the presentation better than haemophilia carrier status already does.