The Union Flag flaps in the wind outside the Houses of Parliament in London on Monday, October 24, 2022. A tribunal said on Monday that British spies unlawfully retained people's intercepted data over almost five years and blamed widespread corporate failure at the domestic intelligence agency MI 5 and the interior ministry.
The Investigatory Powers Tribunal, which did not mention specific cases or intelligence targets in its written judgment, said there had been serious failings in compliance by MI 5 from late 2014 to April 2019.
Judge Andrew Edis said the Home OfficeHome Office did not make adequate enquiries while approving the bulk surveillance warrants from 2016 to April 2019.
Human rights groups Liberty and Privacy International, which brought the legal action, said the ruling showed that there had been years of rule-breaking by MI 5, which was overlooked by the Home OfficeHome Office.
The case related to data obtained in bulk under the Investigatory Powers Act and previous legislation that governs the interception of data for national security purposes.
Britain has been at the forefront of a battle between privacy and security since the former US security agency contractor Edward Snowden leaked details of mass surveillance tactics used by US and British agents in 2013.
READ MORE: EU top court: Spies can snoop on phone data in a crisis.
The Investigatory Powers Act provides vital tools to protect the public from criminals and terrorism, government and security officials say. It grants police and spies some of the most extensive snooping capabilities in the West, according to critics.
On Monday, Home Secretary Suella Braverman said the ruling related to widespread corporate failings between the Home OfficeHome Office and MI 5 was historic In a written statement to parliament, she added that the tribunal found that it was not the case that MI 5 should never have held the material, but that some small part of it had been retained for too long. The tribunal also dismissed Liberty and Privacy International's wider challenge to safeguards under the Investigatory Powers Act and its predecessor.
It refused to quash warrants that might have been unlawfully issued or direct MI 5 to delete any unlawfully retained data, because it would be very damaging to national security.