From today's opinion in Houston Community College System v. Wilson:
[A] plaintiff pursuing a First Amendment retaliation claim must show, among other things, that the government took an "adverse action" in response to his speech that "would not have been taken absent the retaliatory motive." Some adverse actions may be easy to identify—an arrest, a prosecution, or a dismissal from governmental employment. "[D]eprivations less harsh than dismissal" can sometimes qualify too. At the same time, no one would think that a mere frown from a supervisor constitutes a sufficiently adverse action to give rise to an actionable First Amendment claim.
To distinguish material from immaterial adverse actions, lower courts have taken various approaches. Some have asked whether the government's challenged conduct would "chill a person of ordinary firmness" in the plaintiff 's position from engaging in "future First Amendment activity." Others have inquired whether a retaliatory action "adversely affected the plaintiff's … protected speech," taking into account things like the relationship between speaker and retaliator and the nature of the government action in question. But whether viewed through these lenses or any other, it seems to us that any fair assessment of the materiality of the Board's conduct in this case must account for at least two things.
First, Mr. Wilson was an elected official. In this country, we expect elected representatives to shoulder a degree of criticism about their public service from their constituents and their peers—and to continue exercising their free speech rights when the criticism comes. As this Court has put it, "[w]hatever differences may exist about interpretations of the First Amendment, there is practically universal agreement" that it was adopted in part to "protect the free discussion of governmental affairs." When individuals "consent to be a candidate for a public office conferred by the election of the people," they necessarily "pu[t] [their] character in issue, so far as it may respect [their] fitness and qualifications for the office."