Jersey police say new measures have been introduced to ensure there won't be any unlawful raids in future.
It comes after the authorities were heavily criticised for illegally searching premises allegedly linked to Roman Abramovich.
Police were granted search warrants and investigated premises linked to the Russian billionaire in April 2022, seizing documents and devices.
But Reuters reported that in a consent order dated November 9, Jersey police acknowledged that "the search warrants were obtained unlawfully" and agreed "that the search warrants should be quashed".
An apology was issued and damages were paid.
The government says it's taken advice from independent lawyers and is satisfied that the police have come up with steps to ensure such operational errors never happen again.