The prosecution of a teacher for allegedly murdering a baby he was adopting ‘rests on a theory of circumstantial evidence’, a court heard today.The case against Jamie Varley, 37, over the death of Preston Davey, aged 13 months, has been ‘fatally undermined’ after analysis by alternative expert witnesses, said Nicholas Johnson KC, defending.Varley is charged with murder, manslaughter, causing grievous bodily harm, sexual assaults, cruelty, making indecent images and sharing one image with his partner and fellow adoptive father, John McGowan-Fazakerley, 32.Mr Johnson said to jurors at Preston Crown Court: ‘On a fair and detailed analysis, the proper verdicts are not guilty.‘This will always be a deeply shocking, tragic case and we can’t bring Preston back. 'It would be even more tragic to convict a man of previous good character when you are not actually sure on the evidence and you are filling a gap with emotion.’Mr Johnson pointed to a 2023 provisional finding that the cause of Preston's death on July 27 that year was ‘unascertained’.He said pathologist Dr Alison Armour’s conclusion that Preston’s airways had been blocked by an object placed in his mouth, smothering him to death and bruising his throat was ‘circumstantial evidence’.It could have been caused ‘inadvertently’ by use of a laryngoscope, a tube used during intubation to attempt to resuscitate the baby boy, Mr Johnson said.