Thames Valley Police has conceded that search warrants used to raid the homes of Andrew Mountbatten-Windsor at the time of his February arrest were unlawful, the High Court heard on Thursday.

This development stems from a legal challenge launched by the former prince over the legality of the search warrants. Mountbatten-Windsor was arrested on suspicion of misconduct in public office and has consistently denied any wrongdoing.

During a High Court hearing, it was revealed that an agreement had been reached between Mountbatten-Windsor's legal team and the police acknowledging the warrants' unlawfulness. However, the court emphasized that quashing the warrants does not end the ongoing criminal investigation.

The implications of this ruling mean that while the initial basis for the searches was flawed, the items seized, including documents and electronic devices, will remain with the police. A further hearing is scheduled for 2027 regarding the seized property.

Thames Valley Police had applied for search warrants under sections eight and nine of the Police and Criminal Evidence Act 1984 at the Central Criminal Court. The court initially granted warrants only under section eight, but a subsequent legal challenge established that section nine should have been used.

Mr Justice Hilliard explained the court's decision to allow police to retain the seized items, stating that property obtained through an unlawful search can still be held if it could have been lawfully seized under a different provision. He added that returning property only for it to be immediately re-seized under another lawful provision would serve little purpose.

Mountbatten-Windsor's arrest followed the publication of US Department of Justice documents suggesting he had forwarded confidential information to Jeffrey Epstein in 2010, while serving as a UK trade envoy. He has always denied any wrongdoing in his association with Epstein.

A spokesperson for Thames Valley Police clarified that the agreement to quash the warrants pertains specifically to the legal basis used by the court and does not reflect a judgment on the merits of their ongoing investigation. The force maintained that all necessary information and paperwork were presented to the court through the correct legal processes.