The home secretary has launched a legal challenge against the decision to allow the radical preacher Abu Qatada to stay in the UK.
Last month the special immigration appeals commission ruled Qatada should not be deported to Jordan, where he was convicted of terror charges in his absence in 1999, because there was a risk evidence obtained by torture would be used against him in a retrial.
Theresa May submitted grounds for a challenge to the court of appeal in an attempt to overturn SIAC's decision. The only way the ruling can be challenged is if it is found that there were legal problems with the commission's ruling.
The SIAC judges ruled on 12 November that evidence from Qatada's former co-defendants Abu Hawsher and Al-Hamasher, said to have been obtained by torture, could be used against him in a retrial.
"The secretary of state has not satisfied us that, on a retrial, there is no real risk that the impugned statements of Abu Hawsher and Al-Hamasher would be admitted probatively against the appellant," they said.
May immediately pledged to appeal and told the Commons that day that Jordan had given assurances about its legal processes.
She said: "Qatada is a dangerous man, a suspected terrorist, who is accused of serious crime in his home country of Jordan.
"The British government has obtained from the Jordanian government assurances not just in relation to the treatment of Qatada himself, but about the quality of the legal processes that would be followed throughout his trial. We will therefore seek leave to appeal."
Qatada was granted bail following the ruling and released from Long Lartin prison in Worcestershire, returning to his family home in north London.
He is said to have wide and high-level support among extremists, and featured in hate sermons found on videos in the flat of one of the 11 September bombers.
The extremist has battled deportation for more than a decade.