News focus: Big Brother watch - time for intercept evidence to be admissible in court?

Sometime in 2019 or early 2020, users of EncroChat, a smartphone app marketed for the purpose of enabling ‘complete anonymity’, began installing what they thought was a software update. For many, it was a mistake. The ‘update’ was malware developed by a joint team of French and Dutch cyberspooks that extracted users’ messages from their phone’s temporary memory (RAM), where they were stored before being encrypted.

Millions of such messages were made available to law enforcement agencies, including the Metropolitan Police. In a triumphant announcement in July 2020, Europol revealed that police had been reading messages ‘over the shoulder of the unsuspecting senders’. Thousands of arrests were made: thwarted criminal activities included ‘violent attacks, corruption, attempted murders and large-scale drug transports’.

The shadowy providers of EncroChat had already vanished after advising customers to dispose of their phones.

Evidence gathered from the EncroChat hack has helped obtain convictions in England and Wales. But it also exposed the anomalous position of the admissibility of such evidence in English law.

Intercepts – defined as ‘making available the content of a communication to someone other than the sender or intended recipient during the course of its transmission’ – are not admissible as evidence in English courts. This makes the jurisdiction an international outlier. It is especially odd as the UK has long been a world leader in signals intelligence.

Two justifications are advanced for this policy. One is that producing intercept evidence in court would give too much away about technical capabilities. The Gazette understands that security services are especially coy about the state of the art of artificial intelligence used to scan data in bulk while coping with multiple languages and code words.

'I have never seen a sustainable reason against the use of intercepts as evidence in cases of serious crime, including terrorism'

David Bickford, former legal director of MI5 and MI6

The second justification is the cost of converting snooping systems into a regime that would produce evidence robust enough to be produced and scrutinised in court. A Privy Council study for the Home Office in 2014 noted that intelligence agencies ‘are not required to examine, record, retain and review intercept material to the high evidential standard that would be necessary under an intercept as evidence regime’. It calculated that such a setup would cost between £4.25bn and £9.25bn over 20 years and the benefits would be uncertain.

The study found that: ‘On some assumptions the model could lead to an increase in convictions; but on others the model could lead to fewer convictions than at present, due mainly to the compromise of sensitive techniques and the inability to prosecute cases where these techniques had been used.’  

Parliament heard last year that the findings of the 2014 review remain valid. ‘It is not possible to find a practical way to allow the use of intercept evidence in court,’ home office minister Baroness Williams of Trafford said.

Of course, as the EncroChat convictions (and ongoing criminal trials) suggest, it is sometimes possible to admit intercepts as evidence in English courts. One loophole, cited by His Honour Peter Ross in a letter to The Times, is where evidence has been obtained lawfully overseas. He referred to a drugs case where, ‘as the evidence was properly obtained according to Dutch law and admissible in their courts, I ruled it could be adduced in the trial’. The Court of Appeal agreed, he noted, describing the UK’s position as ‘nonsensical’.

At least some of the EncroChat prosecutions face the difficulty that material was obtained in the UK. The lawfulness of its admission has already been challenged. However, in A, B, D & C v Regina [2021] the Court of Appeal found last year that such material could be admitted because it was not, under the terms of the Investigatory Powers Act 2016, ‘being transmitted’ when it was collected. This relied on the technicalities of the EncroChat app and that it stored messages in smartphones’ RAM before encryption and transmission.

However, a policy change may be in the air. Official enthusiasm about the EncroChat trove has eroded the decades-old policy of extreme secrecy about signals intelligence. (The secret of Bletchley Park (pictured above) was kept until the 1970s; current guidance on telecommunications interception remains ‘neither confirm nor deny’.)

One argument for change is that admitting intercept material as evidence will force more transparency on the process and thus build public confidence. Up to now, this argument has failed to persuade the powers that be. But earlier this month, a former legal director of MI5 and MI6 entered the debate. In a letter to The Times, David Bickford wrote: ‘I have never seen a sustainable reason against the use of intercepts as evidence in cases of serious crime, including terrorism.’ The costs argument, he said, ‘fails in the face of the heavy economic damage that can be wreaked by serious criminals and terrorists’.

Perhaps Big Brother is listening after all.