The hierarchy is real
NHS hospital medicine runs on a formal hierarchy in which consultants hold the ultimate clinical authority for patients under their care. Junior doctors, nurses, and other clinical staff operate within a framework consultants set. This is not a pejorative description; it is the structure that makes the NHS functional. Consultant decisions are meant to reflect the deepest clinical expertise in a team, and escalation to consultants is built into every patient-safety protocol.
The hierarchy also has a well-studied shadow side. Nurses who disagree with consultant assessments face material professional consequences for pressing the disagreement. Junior doctors who disagree face the same. The system’s default is that consultant belief, once formed, prevails unless a formal escalation succeeds in dislodging it.
What this means for cluster investigations
A cluster of unexplained deaths on a ward can be read in two ways: as a systems-failure signal (the unit is struggling with acuity, outbreak, staffing, infrastructure) or as a bad-actor signal (a specific person on the ward is responsible). Both readings are possible. The reading a consultant team adopts is the reading that will propagate through the institutional response — because the system is structured to make that so.
At the Countess of Chester, consultant paediatricians came to adopt the bad-actor reading by early 2016. The systems-failure reading was available and was, in retrospect, substantially correct — the Guardian investigation and the Thirlwall Inquiry evidence have documented it. But once the consultant team had adopted the bad-actor reading, the structure of the NHS was such that the reading began to shape every subsequent event: the thematic review, the HR grievance, the RCPCH scoping, the Cheshire Police briefing, and ultimately the jury instruction.
How consultant belief becomes investigative evidence
When police are eventually engaged, their evidential starting point is the briefing from the hospital. If the briefing is a bad-actor briefing, the investigation that follows will be a bad-actor investigation. This is the Allitt framing effect at the operational level: the initial consultant belief becomes the frame under which Operation Hummingbird operated.
At trial, the Crown adduced the consultants’ belief as supporting evidence. The jury was told “these senior doctors who cared for the babies thought it was her”. That framing invites the jury to treat consultant belief as near- independent corroboration of guilt. But consultant belief, in a doctor–nurse hierarchy, is not near-independent; it is the thing that has been producing the evidence the jury is hearing.
The specific concern about circularity
The circularity argument runs: (1) consultants form belief that Letby is harming babies; (2) consultants press executives to act on the belief; (3) executives commission external review but do not contact police; (4) consultants continue to press; (5) police eventually engaged, with briefing shaped by the consultant belief; (6) forensic expert instructed within that frame; (7) expert produces causation opinion consistent with the frame; (8) at trial, consultant belief and forensic opinion presented as mutually corroborating; (9) jury convicts on the combined weight.
At no step from (1) to (9) is there an independent blinded review by specialists who did not start from the consultant frame. The Shoo Lee Panel is the first such review — and it reaches the opposite conclusion from the consultant frame.
Why this is not a criticism of the consultants
Dr Brearey and his colleagues were doing their professional duty in raising the concerns. The Panel’s systems-failure reading does not contradict the fact that the unit had serious problems; it contradicts the bad-actor hypothesis as the explanation for those problems. The distinction between “something is wrong on this unit” (correct, and the consultants were right) and “this particular nurse is doing it” (which is what the conviction rests on) is the whole point the post-conviction review is making.
Nursing colleagues’ perspective
The nursing-workforce perspective captured at the Thirlwall Inquiry — see our evidence page — is that Letby was a competent and caring colleague, and that the unit’s problems were systemic rather than individual. That perspective has been largely absent from public discussion, because in a doctor–nurse hierarchy, the nursing view has less institutional weight than the consultant view. This asymmetry is itself a feature of the record that the CCRC review engages.