The Supreme Court has agreed to hear a case that could determine whether users can challenge social media companies on free speech grounds. The case, Manhattan Community Access Corp. v. Halleck, No. 17-702, centers on whether a private operator of a public access television network is considered a state actor, which can be sued for First Amendment violations. The case could have broader implications for social media and other media outlets. In particular, a broad ruling from the high court could open the country’s largest technology companies up to First Amendment lawsuits. That could shape the ability of companies like...