British counter-terror police on Thursday launched a criminal investigation into documents seized from the Brazilian boyfriend of a journalist working to publish secrets from US intelligence leaker Edward Snowden.
The development came after Britain’s High Court ruled that material seized from David Miranda, the boyfriend and assistant of Guardian journalist Glenn Greenwald, can only be partially examined by police.
London’s Metropolitan Police said publication of the “highly sensitive” data seized from 28-year-old Miranda during his detention under anti-terror laws at London’s Heathrow Airport on Sunday could cause a risk to life.
“Initial examination of material seized has identified highly sensitive material, the disclosure of which could put lives at risk,” Scotland Yard said in a statement. “As a result the Counter Terrorism Command (SO15) has today begun a criminal investigation.”
Miranda’s nine-hour detention has outraged campaigners for press freedom who have called for an inquiry into why laws designed to stop terrorists were used to interrogate a journalist’s assistant.
Miranda, who had worked with his US boyfriend on the Snowden material, was stopped as he changed planes on his way home to Rio de Janeiro on Sunday. Officials confiscated his laptop, mobile phone, memory cards and other electronic equipment.
Snowden, a former US intelligence contractor, enraged Washington by leaking information on mass surveillance programs by the US National Security Agency as well as Britain’s electronic eavesdropping agency, GCHQ (Government Communications Headquarters).
The Guardian has published a series of reports based on files provided by Snowden, who has been granted temporary asylum in Russia as he bids to escape prosecution in the US.
Britain’s High Court ruled on Thursday that police and the Home Office could partially examine the files seized from Miranda for national security purposes, following a legal bid by the Brazilian to stop them.
The Metropolitan Police welcomed the decision, saying they had obtained “thousands of classified intelligence documents” from Miranda’s seized equipment, and that examining them would allow them to “protect life and national security.”
Miranda’s lawyer Gwendolen Morgan said the ruling was a partial victory as it prohibited British authorities from sharing the information with any foreign government “save for the purposes of protection of national security.”
The Home Office and Scotland Yard now have seven days to prove that the documents raised a genuine threat to Britain’s security, she told reporters outside court.
Separately, David Anderson, Britain’s independent reviewer of terror legislation, announced on Thursday that he was launching an investigation into whether the anti-terror laws used to detain Miranda were “lawfully, appropriately and humanely used.”
Guardian editor Alan Rusbridger said of Miranda’s detention: “It seems to me a clear misuse of a law.”
Speaking at the Edinburgh International Book Festival on Thursday, he said it was becoming “impossible” for journalists to have confidential sources.
“How do I know my conversations with sources are now safe? Well I don’t know. In fact, I know the opposite,” he told the audience.
On July 20 the left-leaning Guardian, under the supervision of GCHQ experts, destroyed the hard drives and memory chips on which its Snowden material had been saved.
The government has confirmed that Cabinet Secretary Jeremy Heywood — Britain’s top civil servant and British Prime Minister David Cameron’s most senior policy adviser — was sent to tell the Guardian — they had to either destroy or return the material, or face legal action.
Cameron has faced calls to address parliament on the matter, while the clampdown on the Guardian has drawn criticism from the EU and the German and Russian governments.