David Miranda's detention at Heathrow airport violated his human rights, the High Court has heard.
Gwendolen Morgan of Bindman Partners said in a witness statement made on behalf of Miranda that Schedule 7 of the Terrorism Act was used "for an improper purpose and was therefore unlawful".
The decision to use it "amounted to a grave and manifestly disproportionate interference" with Miranda's human rights, Morgan said.
The independent reviewer of terrorism legislation said he will examine the detention of David Miranda at Heathrow Airport.
Nick Clegg has backed David Cameron's decision to send a top civil servant to The Guardian to urge them to destroy classified data.
The Guardian journalist whose partner was held at Heathrow Airport hits out at the UK as he gives ITV News his first British TV interview.