MI5 watchdog finds serious failings in handling of agent X

MI5’s watchdog found serious failings in the Security Service’s handling of Agent X, the covert human intelligence source whose case exposed false evidence and a gagging injunction. In a judgment handed down on 2 July 2025, the High Court confirmed that X was a CHIS for MI5 and that MI5 had given false evidence to the court and to special advocates about its dealings with him.

In January 2022, a senior MI5 officer known as Witness A told the court that MI5 had maintained a strict neither confirm nor deny stance over X. That was untrue because another MI5 officer had already told BBC journalist Daniel de Simone in June 2020 that X was an MI5 source. By late 2021, the BBC was preparing to broadcast allegations that X was a dangerous extremist and misogynist who physically and psychologically abused two female partners, and that he told one of them, Beth, that he worked for MI5 in order to terrorise and control her.

Then Attorney General Suella Braverman sought an injunction to stop the BBC naming X. An interim injunction was granted on 16 February 2022 and later made permanent that year, blocking identification while leaving reporting on the substance of the allegations in place. MI5’s false evidence had been relied on in multiple proceedings.

In March 2026, MI5 director general Sir Ken McCallum apologised to Beth and the agency agreed to settle her claim with a confidential damages payment and a private apology. Beth said the money could not repair what she had endured. X had previously been reported to a police force overseas over serious domestic violence allegations involving a previous partner and had made public and private statements suggesting an obsession with extreme violence.

A further inquiry ordered by the Prime Minister in September 2025 was still under way in March 2026. It is examining how MI5 came to give false evidence in three sets of legal proceedings and whether any personnel could face contempt proceedings.