"It is the proper legal channel," he said, adding that if the IPT should rule against Privacy International the case can be appealed with the ECHR.
It might be a while before that could happen because cases at the IPT can drag on for seven to eight years, according to Rispoli.
Privacy International has also tried a different route to battle mass surveillance. In November, it filed complaints against U.K. telecommunications companies for assisting GCHQ with mass interception of telephone and Internet traffic that passes through undersea fiber-optic cables.
That complaint was filed with the U.K. office of the Organisation for Economic Cooperation and Development (OECD), which isn't a court and cannot impose sanctions. Privacy International hopes the OECD will investigate and share how the companies participated with the surveillance program.
Privacy International has not hear back from the OECD, Rispoli said.
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