A Worcestershire magistrate has lost his claim against his daughter-in-law for slander and libel over allegations he assaulted her and his baby grandson.
JP Richard Westcott, of Wyre Piddle, Pershore, tried to sue his son's estranged wife Dr Sarah Westcott, of Chalfont St Peter, Buckinghamshire.
But a High Court judge said her oral and written complaints to the police were protected by absolute privilege.
Mr Westcott was interviewed by police in March 2005 but was not charged.
Comments granted absolute privilege under law cannot be treated as defamation.
Dr Westcott, who has obtained a decree nisi from her husband Edward, alleged the incident took place when she took her grandson to Mr Westcott's home for a Good Friday visit to his father.
She said during an argument about her changing the locks at her home Mr Westcott senior "flipped" and lashed out at her as she held her son in her arms.
She took her son to hospital but neither of them had any visible injuries, the court heard.
Richard Westcott's counsel Ken Craig told the court in London that he was concerned he had not had an opportunity to clear his name, as he had not been charged and no trial had been held.
He said Mr Westcott's colleagues knew of the allegations and his position as a magistrate who had previously sat on the Family Panel at Worcester Magistrates' Court.
But Mrs Westcott's counsel said her complaint to the police was legally protected.
Deputy Judge Richard Parkes QC said that there was a legal precedent that priority should be given to the need to allow people to give evidence to the police without fear of being sued.
He said this outweighed the reputation rights of those who were defamed as a consequence.