Ahmed was jailed for life in December 2008 The UK was complicit in the torture of the first al-Qaeda member to be convicted in the country of directing terrorism, a court has heard.
Rangzieb Ahmed, 34, was unlawfully held in Pakistan, beaten and had fingernails removed, a QC told the Court of Appeal.
Joel Bennathan QC said during Ahmed’s torture in 2006 he was asked “many” questions about events in Manchester – where he was arrested a year later.
His trial, which saw Ahmed jailed for life, should have been halted, he said.
Mr Bennathan told the court his client was held unlawfully for more than a year, during which time he was beaten with sticks and cables and had three fingernails pulled out with pliers.
The court heard how the CIA was present at his arrest and how British intelligence officials questioned Ahmed, formerly of Rochdale, during the period of his alleged mistreatment.
“We say the UK was complicit in these acts,” said Mr Bennathan.
He said that in 2006, while his client was being tortured, Ahmed was asked “many, many questions about events in Manchester” which formed a direct link with his subsequent arrest in that city.
When it came to his trial on terrorism charges, “the trial judge should have stayed the proceedings as an abuse of process”, he argued.
He told appeal judges Lord Justice Hughes, Mr Justice Owen and Mrs Justice Thirlwall that they should now allow Rangzieb Ahmed’s appeal “on the same basis”.
Ahmed watched the appeal proceedings via video link from prison.
In July this year Prime Minister David Cameron said a “judge-led” inquiry would look at claims that UK security services were complicit in the torture of terror suspects.
There are approximately a dozen cases involved, including Ahmed’s and the well-documented case of British resident and former Guantanamo Bay detainee Binyam Mohamed.
In December 2008 Ahmed became the first British man to be jailed for directing terrorism outside of Northern Ireland.
He is alleged to have played an important role in Pakistan, linking British activists with Jihadist leaders.
Human rights campaigners in Pakistan highlighted his case before he was deported to the UK to face trial.
The judge at his Manchester trial refused to throw out the case and rejected Ahmed’s claim that his fingernails were pulled before he had been interviewed by MI5.
Earlier this year former Conservative frontbencher David Davis used the legal protection of Parliamentary privilege to make allegations about Ahmed’s treatment, relating to information raised in secret before the trial.
He told MPs that he had information that Greater Manchester Police had sufficient grounds to arrest Ahmed, but he was allowed to leave the UK in 2006.
British intelligence officers then suggested to their Pakistani counterparts that they arrest Ahmed, Mr Davis alleged.
He claimed MI5 subsequently supplied the Pakistani interrogators with questions. And when Ahmed later told visiting MI5 and MI6 officers he had been tortured, they did not return.
“A more obvious case of outsourcing of torture, a more obvious case of passive rendition, I cannot imagine,” Mr Davis told MPs.
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