Focus on what works
While nobody is going to argue that as much as possible shouldn't be done to protect everyone - but especially more vulnerable people - online, it's far from proven that the addition of such a button would have prevented this event.
As we said, Facebook has been extensively criticised for not introducing this button, but it argues that the measures it already has in place are no less effective. Following the clamour for the CEOP button, we received the following statement from a Facebook spokesperson:
The safety of Facebook users is our top priority. We have reporting buttons on every page of our site and continue to invest heavily in creating the most robust reporting system to support our 400 million users. We work closely with police forces in the UK and around the world and have trained staff on two continents giving 24 hour support in 70 languages.
The central issue here, not just concerning Facebook but every form of interaction on the web, is that we're usually not dealing with something that's unique to the Internet; it's more that all kinds of human interaction that also happen off-line are facilitated by sites like Facebook.
So, as well as malign examples like this one, and things like cyber-bullying, we also get positive interactions and grass-roots campaigns like the one that got RATM to number one in the music charts last Christmas.
Facebook has tested universal buttons before and insists that in all its tests it received fewer reports than when using its own system. As a consequence, Facebook thinks the CEOP button is still a good thing, but for sites that don't have the kind of reporting infrastructure Facebook already has.
This is obviously a very emotive issue and it's right that there should be a clamour for more to be done when tragedies like this occur. But by focusing on one measure we risk losing sight of the fact that common sense, healthy paranoia and the need to supervise the vulnerable are all required to minimise risks to online safely.