Fast-moving technological innovations with major social impact pose a challenge to the U.S. legal system, which often has difficulty fashioning a timely and appropriate response, especially if the innovations create opportunities for new forms of social mischief. Courts have a poorly understood but critical role in providing clarity to any response. This article examines the role of the courts in interpreting Section 230 of the Communications Decency Act, and the implications of that role for the current policy debate over Section 230 reform.