A British judge has ruled that a terrorism suspect cannot take secondary-school level courses in chemistry and human biology.

In a first-of-a-kind ruling, High Court judge Stephen Silber said that the courses would put the suspect — who is referred to as A.E. for privacy reasons — in a “substantially stronger position” to carry out chemical and biological attacks.

But scientists are unconvinced. An AS level in human biology is unlikely to provide much in the way of skills to a potential terrorist, says Charles Penn, a molecular microbiologist at the University of Birmingham. “I'm pretty sceptical that this is a real, tangible risk,” he says.

The ruling paints a “misleading image of school chemistry being a subject of particular value to potential terrorists”, says Richard Pike, chief executive of the Royal Society of Chemistry. “There is nothing on the AS-level chemistry course that cannot be found easily on the web and through other means,” he says.

A.E. is an Iraqi national with alleged ties to terrorist groups including Al-Qaeda in Iraq, according to the UK government. Since 2006 he has been subject to a 'control order', a special legal instrument that places limits on his freedoms, including his Internet use. He is subject to surveillance and must seek approval from the Home Office before undertaking coursework.

In September 2007, he asked for permission to enrol in AS-level courses in chemistry and human biology. In Iraq, A.E. had been training as a doctor and the courses were the first step in continuing his education, according to his solicitor, Mohammed Ayub, of Chambers Solicitors in Bradford. The Home Office denied his request, claiming that knowledge gained in the coursework could be used for terrorism. A.E. contested the decision in court, claiming that AS-level courses were largely harmless (see _Nature_ 450, 467; 2007).

The 15-page ruling, released on 21 July, upholds the Home Office's claim. Based in part on testimony from an anonymous security official known only as 'X', Justice Silber found that A.E. would gain expertise, particularly in using equipment, that might further terrorist activities. But Penn questions how useful the courses would be for a would-be terrorist. Even university-level students would have trouble producing large quantities of a pathogen such as anthrax, he says, “they wouldn't have a clue where to start”.

Silber also called into question A.E.'s previous medical training in Iraq, which had been a key part of A.E.'s argument — his lawyer maintained that the AS-level courses would review information he had already learned. Even if A.E. could learn new techniques from the courses, Ayub adds, he is under such tight scrutiny that he would be unable to do much. “The risk is negligible to nil,” he says.

Ayub says that his client is “dismayed” by the ruling, and they are likely to decide whether to take the case to the Court of Appeal within the coming weeks.