Dr Julian Lewis: Until now, the approach even of the more responsible internet companies has been that somebody else has to report something first, and then they will consider taking it down. Surely they should be proactive. If people can search for vile material and find it, why can the companies not search for it proactively and then take it down?

[The Secretary of State for the Home Department (Sajid Javid): My right hon. Friend is right. We have seen some good examples. As I mentioned, Facebook is starting to use machine learning and artificial intelligence to track down this material and, in some cases, even prevent it from being uploaded in the first place. Given that this challenge is caused by technology – much of which we embrace – we should be using more technology to tackle it.]