The government of the United Kingdom may have exploited its access to intercepted, legally privileged communications in order to give itself an unfair advantage in legal proceedings, a tribunal heard on Thursday.
New documents reveal that the intelligence agencies hold policies for spying on confidential communications between lawyers and their clients.
The disclosures were made at a rare open hearing of the investigatory powers tribunal at the Royal Courts of Justice in London. The court normally meets in secret and hears complaints made about surveillance by Britain's intelligence agencies.
The confidentiality of such communications is protected under legal privilege — a central principle of British law. However, if the security services intercept these exchanges, they could provide the government with an unfair advantage in court.
In summaries of intelligence agency policies released to the tribunal, the government admits that there has been at least one case where "the potential for 'tainting' was identified."
The documents, obtained by VICE News, add that "additional procedures" were subsequently established to "safeguard the integrity of the litigation," but do disclose the nature of those procedures.
The documents have been passed to lawyers acting for the Libyan politician Abdel Hakim Belhaj, who are concerned that legally privileged communications may have been intercepted and exploited by the intelligence agencies in a separate claim brought by their client.
Belhaj is a Libyan dissident who led a failed insurgency against former dictator Muammar Qaddafi before fleeing to Malaysia with his Moroccan wife, Fatima Bouchar, in 2004. They were arrested at Kuala Lumpur airport, transferred to Bangkok and placed in the custody of the CIA.
The pair was then secretly rendered to Tripoli, Libya, in a joint MI6-CIA operation, where Qaddafi's security forces tortured him, and it is alleged, British intelligence officers took part in his interrogation.
In 2011 Belhaj, 48, attempted to sue the UK government over claims he was illegally rendered to Libya and tortured. His claim was struck down in 2013, but last month the Court of Appeal ruled that the case should go ahead.
Belhaj is seeking nominal damages of just £1 and an apology from the British government.
Describing the Belhaj case as the "tip of the iceberg," Dinah Rose QC, for Belhaj, said that the most recent policies "do not adequately provide for proper information barriers [between] those handling litigation and those who received the intercepted legally privileged material.
"These policies raise a strong prima facie case that there's been abuse of process and that real injustices may have been done," Rose added.
The summary policies for MI5, the UK's domestic intelligence agency, indicate that an attempt was made to introduce a so-called "Chinese walls" policy, protecting the transmission of legally privileged communications to government lawyers.
"It appears that an attempt was made in 2010 to introduce a Chinese walls policy, but by April 2011 it had been explicitly abandoned," Rose said. "The policy that applied throughout most of the early stages of my own client's claim was the April 2011 policy."
The change in policy is significant because it indicates that fewer safeguards were in place to prevent the abuse of legally privileged material in the Belhaj case.
"It's now clear the intelligence agencies have been eavesdropping on lawyer-client conversations for years. Today's question is not whether, but how much, they have rigged the game in their favor in the ongoing court case over torture," Cori Crider, a director at legal charity Reprieve and US counsel for Belhaj told VICE News.