Samina Malik, the self-styled “Lyrical Terrorist” who wrote poetry about beheading Western hostages, could be one of the first beneficiaries of yesterday’s Court of Appeal judgments.

Malik, 23, became the first woman to be convicted under terrorism legislation since the beginning of the War on Terror in 2001, not so much for the violent poetry that she wrote but the extremist Islamist literature, including the Mujahidin Poisons Handbook and a sniper rifle manual, on her computer.

She was convicted at the Old Bailey under Section 58 of the Terrorism Act 2000. Peter Clarke, head of Scotland Yard’s Counter-Terrorism Command, welcomed her conviction and said: “Merely possessing this material is a serious criminal offence.”

The Appeal Court ruled yesterday, however, that merely possessing such literature was not an offence.

Matthew Parris, the Times columnist, was one of the first to air concerns about Malik’s conviction, asking whether she had been found guilty of a “thought crime”. Muhammad Abdul Bari, secretary-general of the Muslim Council of Britain, agreed. He told The Times young Muslims were being criminalised for having “silly thoughts”.

Malik, who was given a suspended jail sentence, is likely to appeal soon.

The rulings also have serious implications for a number of cases under investigation or awaiting trial. There are at least six suspects awaiting trial under Sections 57 and 58 of the 2000 Act and defence lawyers in each case will be studying the judgment to see if the cases against their clients can be challenged.

Chris Huhne, the Liberal Democrat home affairs spokesman, criticised the Terrorism Act 2000 as “another example of how the Government’s kneejerk drafting of new terrorist offences can lead to confusion from prosecutors and the waste of taxpayers’ money”.

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