A London judge has ruled that search warrants obtained in an investigation involving Andrew Mountbatten-Windsor were unlawful, according to The New York Times.
The judge said a "significant error" had been made when the warrants were granted. The finding concerns the legal process through which police secured authority to search the properties.
The ruling does not, on the information reported, set out wider conclusions about the investigation itself. It instead identifies a flaw in the judicial authorisation of the searches.
The case places renewed focus on the safeguards governing police search powers and the role of courts in reviewing applications for warrants in the United Kingdom.