4 MOODY v. NETCHOICE, LLC Opinion of the Court brought under the First Amendment. As explained below, the question in such a case is whether a law’s unconstitutional applications are substantial compared to its constitutional ones. To make that judgment, a court must determine a law’s full set of applications, evaluate which are constitutional and which are not, and compare the one to the other. Neither court performed that necessary inquiry. To do that right, of course, a court must understand what kind of government actions the First Amendment prohibits. We therefore set out the relevant constitutional principles, and explain how one of the Courts of Appeals failed to follow them. Contrary to what the Fifth Circuit thought, the current record indicates that the Texas law does regulate speech when applied in the way the parties focused on below—when applied, that is, to prevent Facebook (or YouTube) from using its content-moderation standards to remove, alter, organize, prioritize, or disclaim posts in its News Feed (or homepage). The law then prevents exactly the kind of editorial judgments this Court has previously held to receive First Amendment protection. It prevents a platform from compiling the third-party speech it wants in the way it wants, and thus from offering the expressive product that most reflects its own views and priorities. Still more, the law—again, in that specific application—is unlikely to withstand First Amendment scrutiny. Texas has thus far justified the law as necessary to balance the mix of speech on Facebook’s News Feed and similar platforms; and the record reflects that Texas officials passed it because they thought those feeds skewed against politically conservative voices. But this Court has many times held, in many contexts, that it is no job for government to decide what counts as the right balance of private expression—to “un-bias” what it thinks biased, rather than to leave such judgments to speakers and their audiences. That principle works for social-media platforms as it does for others. In sum, there is much work to do below on both these