Knife and gun amnesties don't work

I am very much enjoying the BBC's Open Secrets blog. Martin Rosenbaum has been using FoI requests to turn up all sorts of stuff.

Some of it is amusing (for instance, Ken Livingstone's letter informing the President of Venezuala that Londoners are "moved" by Chavez's policy on eye care, which I am sure we would be if any of us had heard of it), some of it minor but eyebrow raising (a rave review of David Cameron's India trip from FCO diplomats).

At its best, however, the blog is really revealing. This post on knife and gun amnesties is important, for example. It provides police evidence that they don't work. And tucked away in one of the papers is the information that knife crime actually went up during the period that the British Transport Police trialled metal detectors on the London Underground.