The Measure of Government Speech: Identifying Expression\u27s Source

States and other governmental bodies increasingly invoke the government speech defense to First Amendment challenges by private parties who seek to alter or join what the government contends is its own expression. These disputes involve competing claims to the same speech: a private party maintains that a certain means of expression reflects (or should be allowed to reflect) her own views, while a public entity claims that same speech as its own, along with the ability to control its content. In suggesting a framework for approaching these problems, this Article starts by examining the theoretical and practical justifications for insulating government speech from First Amendment scrutiny. It addresses the benefits of government speech in facilitating self-governance so long as such speech remains subject to political accountability checks like petitioning and voting. It also explores the body of social science research that describes how a message\u27s source shapes its effectiveness, with special attention to the government\u27s role as the source -- or perceived source -- of a particular view. Emphasizing that government speech is most valuable and least dangerous when its governmental source is apparent, the Article then proposes that a public entity seeking to claim the government speech defense must establish that the contested expression is governmental in origin both formally (i.e., that the government expressly claimed the speech as its own when it authorized the communication) and functionally (i.e., that onlookers understand the speech to be the government\u27s at the time of its delivery). This dual requirement maximizes prospects for meaningful credibility assessment and political accountability by identifying two junctures at which government must expose its expressive choices to the public: when it decides to express a certain idea and when it actually communicates that idea. The Article then draws from relevant experience in other areas to examine a variety of characteristics -- or source cues -- that may signal a message \u27s genesis as governmental or private. These include not only express indications of a message \u27s origin, but also less direct signals like a message \u27s physical location or onlookers\u27 expectations based on past practice. The Article goes on to apply this framework to several recurring challenges, exploring specific features in a range of contexts that may obscure or reveal a message\u27s governmental source