In their contribution to the volume Human Rights, Digital Society and the Law, Matthias Kettemann and Wolfgang Benedek show that freedom of expression is a central right of the information society and that states and companies have certain obligations to protect it.
States have a duty to protect their citizens with regard to the Internet (and regarding their online activities, including the exercise of freedom of expression). In so doing, they are obliged to protect them from the activities of third parties as well, be they other individuals or companies. Tech companies, too, including social networking platforms, have a corporate social responsibility to respect human rights within their sphere of influence, which – on the Internet – is growing rapidly as the majority of relevant communicative acts takes place in private spaces. The special role of intermediaries is another challenge for regulating the Internet. As the majority of online spaces lies in private hands, it is private law that prima facie frames many norm conflicts online. When states react belatedly through laws or judgments, these may lead to over-blocking or legal conflicts between competing jurisdictions.
Kettemann, M. C.; Benedek, W. (2019): Freedom of Expression Online. In: M. Susi (ed.), Human Rights, Digital Society and the Law. A Research Companion. London: Routledge, pp. 58-74.
You can order this volume here.