When architectural photographer Grant Smith was harassed by security guards and detained by City of London police last December he probably thought it was just happenstance. When it happened again last week he might have considered it coincidence. Now, thanks to a document obtained by the Guardian under the Freedom of Information Act, he knows it was enemy action all along.

The previously unseen document, from police initiative Project Griffin, instructs the City’s 5,000 private security guards to report people taking photographs or making sketches within the City of London. The advice encourages a “culture of challenging suspicious behaviour”, which it defines amongst other things as “people using recording equipment, including camera phones, or seen making notes or sketches”.

All of which helps to explain why so many photographers, and even painters, have recently been stopped and searched in the area by police quoting Section 44 of the Terrorism Act. Nowhere does the document advise that photography and painting remain legal activities in the UK, unlike the police’s frequent misuse of Section 44, which was earlier this year ruled illegal in the European Court of Human Rights.

Such police action against photographers is not just illegal; it’s a waste of resources and displays a bizarre lack of understanding of the tools available to any terrorist involved in hostile reconnaissance. Apart from the huge number of pictures available from subversion organisations like the British Tourist Authority, the Al Qaeda forward intelligence team need only turn to Google Street View for anything they need, including Aldermanbury Square, the scene of Smith’s detention last week.

Here it is, and without the distracting security goons obscuring the view:

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