From the abstract for Douglas McKechnie, @POTUS: Rethinking Presidential Immunity in the Time of Twitter, 72 Univ. of Miami Law Review 1 (2017):
President Donald Trump’s use of Twitter portends a turning point in presidential communication. His Tweets animate his base and enrage his opponents. Tweets, however, like any form of communication, can ruin reputations. In Nixon v. Fitzgerald, the Supreme Court determined that a president retains absolute immunity for all actions that fall within the “outer perimeter” of his official duties. This Article explores the “outer perimeter” of presidential immunity. It suggests the First, Fifth, and Fourteenth Amendments in-form the demarcation of the “outer perimeter,” and that when a president engages in malicious defamation, his speech falls outside this perimeter and is not protected by presidential immunity.
The Article begins by examining Twitter as a social media platform and how it facilitates and affects the way we communicate. It then focuses on how Presidents Barack Obama and Donald Trump incorporated the use of Twitter into their presidencies. I then explore four distinct lines of jurisprudence that I argue inform how to identify the “outer perimeter” of a president’s official duties: (1) presidential immunity; (2) immunity for executive branch officials; (3) the constitutional implications of defamation; and (4) the Fifth and Fourteenth Amendments’ prohibition on government action motivated by animus. I posit that considering these four doctrines, along with the method and manner of communication facilitated by Twitter, malicious defamation falls outside the “outer perimeter” of official presidential duties, and thus, presidential immunity is inapplicable.