Outside Looking In: Approaches to Content Moderation in End-to-End Encrypted Systems. (arXiv:2202.04617v1 [cs.CR])

In this paper, we assess existing technical proposals for content moderation
in End-to-End Encryption (E2EE) services. First, we explain the various tools
in the content moderation toolbox, how they are used, and the different phases
of the moderation cycle, including detection of unwanted content. We then lay
out a definition of encryption and E2EE, which includes privacy and security
guarantees for end-users, before assessing current technical proposals for the
detection of unwanted content in E2EE services against those guarantees.

We …

content moderation encrypted end end-to-end moderation systems