Door-swipe data mislabelling — CPS admission (August 2024)
The prosecution’s claim: Door-swipe records from the Countess of Chester neonatal unit were used at trial to place Lucy Letby on the unit at times material to the indicted counts. The Crown treated the swipe data as objective contemporaneous placement evidence.
Prosecution claim
Door-swipe records from the Countess of Chester neonatal unit were used at trial to place Lucy Letby on the unit at times material to the indicted counts. The Crown treated the swipe data as objective contemporaneous placement evidence.
Counter-evidence
In August 2024 the Crown Prosecution Service confirmed that swipe data for one of the unit's doors had been mislabelled — entries and exits were reversed. Cheshire Police's subsequent review concluded that the incorrect data was relied on in evidence relating to nine infants. The mislabelled data played a central role only in the case of Child K, the count on which Letby was not convicted at first trial; conviction was returned at the 2024 retrial. A second door to the unit did not record entries or exits at all, meaning the swipe-card record cannot account for all movements into and out of the unit during the indictment period. The CPS did not confirm whether data for other doors had been correctly labelled.
"Swipe data for one of the unit's doors had been mislabelled, with entries and exits reversed. The data was relied on in evidence relating to nine infants." — Crown Prosecution Service confirmation, August 2024
What the jury heard
Swipe-card records were presented as part of the documentary evidence placing Letby on the unit. The jury was not told the door-record system had been mislabelled or that a second door recorded nothing.
What the Panel says
The Shoo Lee Panel did not opine on door-swipe records (a documentary not a medical issue). The mislabelling is a documentary-evidence ground separate from the medical-causation findings.
What independent experts add
- The CPS confirmed entries and exits were reversed for one door; the police review concluded the bad data was used in evidence relating to nine infants.
- The mislabelling was central to the Child K count (a re-tried count on which conviction was returned at retrial in 2024).
- A second door on the unit did not record entries or exits at all, leaving a documented gap in the swipe-card record.
- The mislabelling was confirmed publicly in August 2024 — after the original trial and around the time of the Child K retrial — meaning the original jury could not have heard the corrected position.
- Under the unsafe-conviction standard the Court of Appeal applies on CCRC referral, contemporaneous documentary evidence the jury heard but which is later confirmed to be wrong is material to safety.