The likes of Facebook must stop under-18s from sending each other sexually explicit pictures, UK health secretary Jeremy Hunt has told a Parliamentary committee.

Giving evidence to the Health Select Committee about suicide prevention yesterday, Hunt demanded that social media companies must take responsibility for stopping teens from being teens.

"I just ask myself the simple question as to why it is that you can't prevent the texting of sexually explicit images by people under the age of 18, if that's a lock that parents choose to put on a mobile phone contract. Because there is technology that can identify sexually explicit pictures and prevent it being transmitted," he was quoted as saying by the Press Association (reproduced on the Guardian).

Although the popular and well-respected (ahem) health secretary did not elaborate, it is likely he was thinking of the content-blocking systems used by ISPs to stop access to child abuse imagery.

One common implementation is to scan networks for the hashes of known child abuse images, typically using lists of hashes provided by organisations such as the Internet Watch Foundation.

Applying this to one's own nude selfies would be impossible, not least because nobody external can determine the hash of a freshly created image. The IWF hash list works on the basis that very little child abuse imagery is new and most of it is traded between paedophiles again and again, allowing police to get copies of the images and pass them to the IWF for analysts to classify them and determine their hashes.

"I ask myself why we can't identify cyberbullying when it happens on social media platforms by word pattern recognition, and then prevent it happening," Hunt told the select committee. "I think there are a lot of things where social media companies could put options in their software that could reduce the risks associated with social media, and I do think that is something which they should actively pursue in a way that hasn’t happened to date."

Telling teenagers they are not allowed to do something in order to stop them from doing it has been a uniquely unsuccessful strategy for parents and governments alike throughout human history. Hunt, a father of three, presumably hasn't yet worked this out.

Meanwhile, webcam-based sexual extortion (sextortion) is on the rise, with 900 cases being reported so far this year – more than double the figure for 2015.

The basic premise is that the mark is duped into performing a sex act on webcam and then forced to carry out actions dictated by the blackmailer on pain of the captured footage being sent to the mark's friends, family and colleagues.

Assistant Commissioner Martin Hewitt, speaking for the National Police Chiefs' Council, said: "This is a really worrying, emerging new threat. As a result to this crime we've already had four young men in the UK kill themselves because they saw no way out of the situation they had got themselves into." ®