A doctor has told the public inquiry into Lucy Letby’s crimes that he felt "ashamed" for "failing to protect" babies from the former nurse.
Consultant paediatrician Dr John Gibbs, now retired, was working at the Countess of Chester Hospital when Letby began attacking vulnerable babies on the neonatal unit in June 2015.
He told the Thirlwall Inquiry that relationships between consultants and nurses became "strained" as babies began to collapse and die without explanation.
He said the parents would now want to know how their children were able to come to harm, rather than receive "belated apologies".
He told the inquiry: "I do deeply regret and I am ashamed that I failed to protect the babies from harm by Lucy Letby, but I do understand that the parents concerned probably now would prefer explanations rather than belated apologies."
Dr Gibbs, who started working in Chester in 1994, said he felt he and his colleagues were "at fault" for not bypassing management in the summer of 2016 when suspicions had been shared with executive directors.
The hospital did not formally contact Cheshire Constabulary for almost a year.
The inquiry heard that emails sent by Dr Gibbs in June 2015 reflected concerns about a "cluster" of three deaths on the neonatal unit that month – infants later referred to as Babies A, C and D.
Dr Gibbs told Lady Justice Thirlwall that around that time it had been noted in "informal discussions" how Letby was present in those cases, as well as the unexpected collapse of another child, Baby B.
However, he said there was no suspicion of deliberate harm by July 2015 and he and his colleagues believed she had simply been "unlucky" and on a "bad run".
But by February 2016, he agreed that concerns had begun to "coalesce" about whether a member of staff was causing deliberate harm.
He told the inquiry he could not remember whether suspicions began to form before the end of 2015, but the "big worry" followed an internal review in February which examined mortality rates and showed a breakdown of how many incidents Letby had been on duty for.
The review also revealed that six babies had deteriorated suddenly between the hours of midnight and 04:00.
He said: "I didn’t realise there had been quite so many deaths either, so the full enormity of it started to hit me when I saw that review."
Dr Gibbs said that at that point, however, he was also conscious that a nurse had been wrongly accused of killing patients in the 2011 Stepping Hill Hospital case, before the correct culprit, Victorino Chua, was eventually jailed.
"You don’t have to have to be a perpetrator to be unfortunate and be on duty when sad events keep happening," he said.
"And I did know that nurse Letby tended to be around on the neonatal unit a bit more than other nurses because she did extra shifts."
He also told the inquiry about the "pushback" from senior nurses when concerns were raised about Letby.
Growing suspicions
"One aspect that made it more difficult to be sure, to try to help confirm those suspicions, was a very strong argument being put forward from the senior nurse on the unit that this suspicion was totally wrong and that we were maligning nurse Letby and she was a very competent safe nurse," he said.
However, the inquiry heard that by the summer of 2016, the deaths of two triplets as well as a series of other inadequately explained collapses, hardened suspicions about Letby.
On 29 June, Dr Gibbs was included in an email chain which discussed specific concerns about Letby and also included medical director Ian Harvey.
In that exchange, Mr Harvey told the consultants, including Dr Gibbs, that the issue was being taken seriously and asked for "all emails to cease forthwith".
Dr Gibbs said on 30 June there was a specific discussion amongst the consultants about whether Letby had been harming babies by injecting them with air bubbles.
He told the inquiry that he now believed that he and the other consultants should have bypassed senior management and contacted the police themselves - a year before hospital bosses actually did so.
Letby, 34, from Hereford, is serving 15 whole-life orders after she was convicted of murdering seven infants and attempting to murder seven others.
The inquiry continues.
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