When Lucy Letby was convicted of murdering seven babies and attempting to murder seven more, much of the case rested on the testimony of one man—Dr. Dewi Evans.
But now, that very testimony is facing intense scrutiny, and the doctor himself is at the heart of an escalating controversy.
A Shocking Outburst That Changed the Conversation
It all took a strange turn recently when Dr. Evans, a retired paediatrician and the prosecution’s lead expert witness, lashed out publicly.
In a bizarre rant directed at a statistical analyst who questioned the validity of his courtroom testimony, Dr. Evans implied that Letby’s defenders were only motivated by her looks.
“It’s not unusual for men to have the hots for pretty young blonde females,” he said, before going on to mockingly suggest the critic should “get out more” and find himself a woman—preferably not one “intent on murdering her patients.”
The comment raised eyebrows not only for its tone but also because it seemed to dismiss serious legal and scientific concerns with casual sexism.
The Case Starts to Unravel
Letby, a nurse at the Countess of Chester Hospital, lost her appeal last year.
But since then, her new legal team has uncovered a wave of evidence that could turn the case on its head.
One big issue? Dr. Evans’ own changing accounts.
He reportedly reversed his explanation of how three of the babies—known as Babies C, I, and P—died.
This shift happened not in early case development, but mid-trial, contradicting years of pre-trial reports. And that’s just the beginning.
The Numbers Didn’t Add Up
The core of the Crown’s case rested on the idea that Letby was present during a suspiciously high number of baby deaths and collapses—25 in total.
But Dr. Evans originally investigated 28 cases, and Letby wasn’t even on shift for ten of them.
That wasn’t shared with the jury.
In one case, even the hospital door-swipe data was wrong.
It showed Letby on the ward when, in fact, she wasn’t there.
The Royal Statistical Society has publicly criticised how these numbers were presented to the jury, and Letby’s legal team believes this statistical framing misled the court from the start.
A Medical Divide: Disputed Theories and Hidden Evidence
Dr. Evans’ claims of insulin poisoning were also challenged.
Paediatrician Dr. Astha Soni said in her undisclosed police statement that one baby’s insulin levels could be explained by a genetic condition—something that directly opposed Dr. Evans’ conclusion of external insulin injection.
That statement never made it to Letby’s defence team.
Since the trial, numerous medical experts, including an international panel led by respected neonatologist Professor Shoo Lee, have reviewed the evidence and concluded there’s no solid basis to say Letby murdered or attempted to murder any babies.
Mounting Legal Pressure and Public Concern
Prominent voices in law are now speaking out. Barrister Adam Kin has called the conviction “almost certainly unsafe,” urging a second appeal.
Even former Supreme Court judge Lord Sumption has weighed in, saying he believes Letby is “probably innocent.”
And Conservative MP David Davis didn’t mince words either, calling Dr. Evans’ recent rant “offensive” and saying it damages his credibility.
“When people lash out like this, it’s usually because they’re not confident in their facts,” Davis said, adding that almost every new detail has served to undermine the prosecution’s narrative.
A Witness With a Questionable Role
Part of the concern lies in how Dr. Evans became involved in the case in the first place.
He wasn’t sought out for his expertise. Instead, he volunteered—writing to the National Crime Agency and describing the case as “his kind.”
His background raised eyebrows. Though experienced in paediatrics, he hadn’t cared for a premature baby since 2007 and never specialised in neonatology.
And during the years he worked on the Letby investigation, his private consulting business reportedly thrived.
He’s even joked on a podcast that he took on expert witness work “to keep my son in cars and my daughter in horses.”
Criticism From Inside the Courtroom
Dr. Evans has a history of being challenged in court.
In a separate case, Court of Appeal judge Lord Justice Jackson accused him of deciding the outcome he wanted before tailoring his report to fit it.
The judge labelled one of his reports “partisan” and claimed Evans ignored other expert opinions or failed to seek them out altogether—a serious breach of professional conduct.
Silence Amid the Storm
Despite the mounting backlash, Dr. Evans hasn’t publicly responded to the latest round of criticism.
He insists he stands by his reports, saying he’s in “huge demand” and has a strong track record.
But even that claim is being questioned now, as his reputation faces heavy damage from inside and outside the legal system.
A Conviction in Crisis
The questions around Dr. Evans’ credibility have now ballooned into a much larger issue: whether the entire case against Lucy Letby was fatally flawed.
Without forensic evidence, and without a clear motive, the prosecution relied heavily on Dr. Evans and statistical correlations to make its case.
But with his credibility in doubt, and new evidence emerging almost weekly, pressure is growing for the justice system to take a second look.
For a case that shocked the nation, it seems the final word may not yet be written.