Social media and gaming firms face a multi-million pound lawsuit for breaching children’s human right to respect for a family life with their “addictive” technology, according to a legal opinion by one of the UK’s top privacy lawyers.

Jenny Afia, a member of the Children Commissioner’s digital taskforce, says the damage caused to family life from denying children sleep and a less active outdoor life to disrupting their schoolwork and mental wellbeing amounts to a breach of article 8 of the Human Rights Act.

She believes the way the firms including Facebook, YouTube and Instagram have designed their technology to be addictive and keep children online would undermine the companies’ first line of defence under the Act that users’ have the free will to switch off their devices.

Her case is backed by evidence not only from psychologists identifying “hooks” like night-time notifications and auto-play videos but also industry insiders such as Facebook co-founder Sean Parker who admitted the applications were “all about consuming as much of [people’s] time and attention as possible.”

Ms Afia, who has represented stars from Madonna and Adele to J K Rowling and Sir Elton John, has specialised in taking on the tech companies, pressuring Instagram to re-write its terms and conditions after reducing its 17 pages of legal-ese to one child-friendly page of plain English. She is willing to take on a family's case herself.