A new DfES policy will give teachers, ‘The legal right to reasonably confiscate inappropriate items from pupils such as mobile phones or music players’. Heads will also be allowed to ‘use airport style metal detector arches and wands to carry out random non-intrusive searches of pupils for weapons’.

With Ken Livingstone calling for all schools to have security scanners this may be a real boost for companies like QineticQ and Chubb, particularly with the announcement that Havering College in London is spending £1m on security and scanners after three students were stabbed. But behind all the rhetoric and business opportunities, there are some glaring inconsistencies. For example, what use are metal detectors, scanners and strict anti-weapons policies when orthodox Sikh students will still be allowed to wear kirpan ceremonial daggers at school?

While the religious importance of kirpans is beyond dispute, having a policy that allows one group of students to bring knives into schools cuts a large hole in the DfES’s anti-knife strategy. The DfES aren’t alone in this area with the Canadian Supreme Court recently ruling that all Sikh students must be allowed to wear kirpans whilst in school.

So carrying knives for religious reasons are OK, but music players, which at worst cause some lax attention and minor disruption aren’t. Alan Johnson may be right in saying schools ‘are safe places’, but his claims that this is ‘clear guidance’ are nonsense. Offering a different and uniquely political perspective on this area is Ken Livingstone, who claims knife crime in schools is a legacy of Thatcherism.

Alan Johnson’s announcement coincides with the education unions’ Easter conference season, but it’s easy to forget that Charles Clarke, then running the DfES, announced something very similar (including providing rewards for good behaviour and supporting teachers falsely accused by students) back in 2004 - how little things change!