Lawyers acting for the partner of a journalist held for nine hours under anti-terror laws will take his case to the High Court tomorrow.
They have applied for an injunction preventing the police or government using, copying and sharing data from electronic devices seized from David Miranda during his detention.
Two judges will also hear their argument that David Miranda's detention at Heathrow Airport was a misuse of Schedule 7 of the Terrorism Act 2000 and breached his human rights.
Mr Miranda is the partner of Guardian journalist Glenn Greenwald who has worked with US whistleblower Edward Snowden on a series of security services exposes.
He was held without charge for the maximum time permitted under the anti-terror legislation as he changed planes on a journey from Berlin to his home in Brazil.