May 2026: Thirlwall Inquiry report delayed to at least September 2026 · six-baby inquests relisted to 2027 · CCRC review active · Shoo Lee Panel: no medical evidence of deliberate harm.
The Crown's insulin theory alleged Lucy Letby added insulin to a TPN (total parenteral nutrition) bag in the ward fridge, from which the bag was then hung for Baby F and subsequently Baby L. The physical mechanism required a contaminated TPN bag.
No TPN bags were retained for forensic chemistry. There are therefore no physical exhibits for the insulin allegation. The Crown's theory rests entirely on the inference from the Roche Cobas immunoassay blood result. Multiple nurses on the unit drew from the same ward-fridge TPN stock; if a bag had been contaminated, identifying which person had contaminated it on forensic grounds would require the physical bag — which does not exist. This chain-of-custody failure is itself a structural problem with the insulin count: the theory requires a physical act on a physical exhibit, and the physical exhibit was not preserved.
You cannot convict on a theory that requires a physical act on a physical exhibit when you have not kept the physical exhibit. There is no insulin-contaminated bag to examine. There never was.
The Crown's narrative of insulin-in-TPN-bag was presented as a plausible mechanism consistent with the Roche Cobas blood result. The absence of physical bag evidence was not systematically flagged as a chain-of-custody failure.
The Joint Insulin Report identifies the chain-of-custody problem as one of multiple reasons the insulin evidence cannot support a criminal finding of exogenous insulin administration.