A man who was previously cleared of killing his wife on the grounds of self-defence has been found guilty of her murder after their child came forward with new evidence under double jeopardy rules.

Robert Rhodes, 52, from Withleigh, Devon, was convicted unanimously at Inner London crown court of murdering his wife, Dawn nine years ago on 2 June 2016.

He was also found guilty of child cruelty by inflicting a wound to a child under 10 – who cannot be named for legal reasons – in an attempt to cover up this crime, perverting the course of justice by causing injuries to himself and the child, and by manipulating the child to cause them to injure him in an attempt to cover up what he had done.

Robert Rhodes manipulated a child under 10 into helping him shield his crime. Photograph: Surrey Police/PA

Police said Rhodes had also been found guilty of committing perjury at the Old Bailey in 2017 and at the family court in 2018 for falsely giving evidence that he knew was untrue.

He will be sentenced at Inner London crown court on 16 January.

The retrial jury heard how Rhodes had originally been acquitted of the murder in 2017 after the original jury believed his account that Dawn had tried to attack him first and he was acting in self-defence.

A main witness in the trial – the child under 10 – told their therapist in November 2021 that their father had planned Dawn’s murder and had manipulated them into being involved in it.

Police said Rhodes described this as “our plan” and then made the child lie about how their mother had died.

In an interview, the child talked about how their father had caused the relationship with their mother to deteriorate and how he had manipulated them into helping Rhodes get rid of their mother.

The child also told police that during supervised contact with Rhodes in 2016 and 2017 – while he was on bail after being charged with Dawn’s murder – he continued to give them instructions to stick to the plan and told them that they had “got some things wrong”.

Police said Rhodes continued to manipulate and groom the child, including hiding a phone at his own mother’s house on which he would leave messages for the child reminding them about the agreement they had made.

Rhodes’s acquittal was quashed in November 2024 and permission was granted for a retrial.

During the retrial, the court heard how the marriage had been in difficulty prior to Dawn’s death and Rhodes had filed for divorce.

Police said the child made a 999 call at 7.34pm on 2 June during which Rhodes said his wife had attacked him and their child with a knife and that he had acted in self-defence.

Police found Dawn Rhodes lying on the kitchen floor with her throat cut to the extent that all the structures in her neck had been severed.

Dawn’s mother, Liz Spencer, said she was “a loving daughter, sister and mother”, adding: “Being a mother was what brought joy to Dawn, she always wanted to be a mother and was delighted when she had her children.

“Dawn was caring, capable and strong. She would do anything for anyone and was loved by both friends and family.”

Clarrie O’Callaghan, co-founder of the Femicide Census, said it was “an amazing result”, adding: “This is a moment when you want to herald that the criminal justice system actually does work sometimes. The police and CPS were tenacious in securing this conviction – the system can work.”