LONDON — Lawyer for convicted British killer nurse Lucy Letby said Monday he plans to ask an appeals court to review his convictions after the prosecution’s lead expert changed his mind about how three babies died.

Dr. Dewi Evans’ testimony is no longer credible after she reversed her opinion that Letby injected air into a nasal gastric tube that killed three infants, lawyer Mark McDonald said.

“I have new evidence that casts doubt on the conviction,” McDonald said. “The defense will argue that Dr. Evans is not a reliable expert, and given that he was the prosecution’s lead expert, we say all convictions are unsafe.”

Letby, 34, is serving multiple life sentences with no chance of release after being convicted of murdering seven babies and attempting to murder seven others while working as a neonatal nurse in Countess of Chester Hospital, in the northwest of England, between June 2015 and June 2016.

Prosecutors said Letby’s methods left little trace and included injecting air into their blood, administering air or milk into their stomachs through nasogastric tubes, poisoning them with insulin and interfere with the breathing tubes. Prosecutors said she represented a “constant malicious presence” and was alone on duty in the neonatal unit when the children collapsed or died.

Letby, who testified at two trials that she had never harmed a child, has maintained her claims of innocence.

McDonald said he had 15 medical experts reviewing the trial evidence.

A ongoing investigation to examine the hospital’s failures to recognize why babies were dying and why it took so long to stop Letby, opened in September amid a backdrop of experts and others questioning the evidence used against Letby.

A group of scientists, doctors and legal experts who independently reviewed the scientific evidence from Letby’s trial have warned Britain’s health and justice ministers that legal systems are “particularly vulnerable to error” when they dealt with technical issues, “particularly in cases involving statistical anomalies in health care.” parameters.”

Evans changed his mind about the cause of death of the infants identified in court as Baby C, Baby I and Baby P, McDonald said. Additionally, two neonatologists working with the defense said there were medical reasons why Baby C and Baby O became ill and could not be resuscitated.

The Crown Prosecution Service defended the verdicts.

“Two juries and three Court of Appeal judges considered a multitude of different pieces of evidence against Lucy Letby,” a CPS spokesperson said in a statement. “In May, the Court of Appeal rejected Letby’s permission to appeal on all grounds – rejecting his argument that the prosecution’s expert evidence was flawed.

McDonald said he will file a motion this week asking the Court of Appeals to reconsider his appeal request. The court twice rejected Letby’s appeal request.