Gwendolen Morgan, of law firm Bindmans, representing Mr Miranda, said outside court that the Home Office and police had made "sweeping and vague assertions about national security".
She said Mr Miranda "does not accept the assertions they have made".
He "looks forward to the opportunity to have the Government's actions and assertions fully scrutinised" at the hearing in October, she added.
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A dry and fine weekend for most, with scattered showers and heavier downpours in Scotland.