Social networks 'cannot be trusted to protect children online' Producer Rachel Seifert, posing as a 13 year old, regularly played the game over a period of two months and said she was subject to sexually explicit language each time. Children as young as eight were believed to be using the site. Habbo Hotel said at the time they employed more than 225 moderators to track conversations on a 24-hour basis. However, Mr Carr said companies cannot be trusted to moderate sites themselves. "I'm increasingly coming to the view that it [self-regulation] is all a big con," he said. At no point in the UK or in Europe have we ever had any independent mechanisms to monitor whether companies who have signed up to voluntary codes of practice or say they are going to behave in a particular way, are in fact doing so. It isn't good enough to take these things on trust, you shouldn't have to take on trust that people are doing what they say they are doing on a voluntary basis. My feeling is that whenever you lift up a stone and look deeply into any of these things, you will find things that are not very pleasant.  Facebook, the leading social network with 901 milion users, does not allow anyone under 13 to sign up. However, studies suggest that 7.5 million children lie about their age in order to join, with more than five million of those aged under 10. The company has hinted that it may introduce a system where by children under 13 can join, but it could build in a system of parental control so parents can decide who children can 'friend'.