Evans is a hired gun who has openly changed his story to suit the prosecution narrative. Some excerpts from: https://www.theguardian.com/uk-news/2024/dec/20/my-kind-of-case-intense-focus-falls-on-lucy-letby-trial-expert-witness
Experts say that causes of babies’ collapses cannot always be explained, even by extensive review, including postmortems.
Asked by the Guardian to explain how he diagnosed air embolism when none of these experts did, from the same medical notes, Evans said he had done so independently.
"Well without being too blase about it, it’s only difficult if you don’t know the answer, OK. Once you know, you know … It’s not very good asking me why I diagnosed air embolus. I think you should be asking other people why didn’t they make the diagnosis.”
He explained that he identified it due to rashes, air observed in some postmortems – although bodies produce air after death – and by excluding other medical causes. But he also acknowledged that air embolism is very difficult to prove: “Trouble is you don’t get evidence: air embolus doesn’t leave any marks, you see.”
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Evans said his new opinion was based on the baby’s sudden collapse and unsuccessful resuscitation on 13 June 2015, on ruling out other possible causes, and realising that Letby was on shift, and had gone into the baby’s room.
“Something must have happened,” he said. “I know that’s not a very scientific term.”
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Responding to the Guardian’s questions about Baby C, Evans stood by his opinions, and wrote in an email: “Lucy Letby murdered Baby C. Get that into your head.”