The 1st amendment isn't a license to abuse freedom of speech.
One cannot yell "fire" in a crowded theater.
One cannot write or say that which untrue about someone, without the risk of facing charges of slander or libel.
If one can prove a charge to be true, then it's not slander, nor is it libel.
If one cannot, they are still certainly entitled to their opinion.
But one CANNOT willfully make a charge so egregiously erroneous that it harms another.
Read this and I have to do it now.
There was a case, an infamous, hysterical but really very important First Amendment case, that hit the Supreme Court wherein Hustler magazine printed a parody of a popular ad suggesting Jerry Falwell got drunk and gave an interview stating he had sex with his mother in an outhouse.
(pause for laughter and/or outrage)
Even in that situation, Falwell lost straight through on his defamation claim. He initially won on intentional infliction of emotional distress, but the Supremies overturned it. Speech that is protected cannot be subject to government sanction, including in civil courts.
In smacking down the award, this is part of what the Court had to say:
"Outrageousness" in the area of political and social discourse has an inherent subjectiveness about it which would allow a jury to impose liability on the basis of the jurors' tastes or views, or perhaps on the basis of their dislike of a particular expression. An "outrageousness" standard thus runs afoul of our longstanding refusal to allow damages to be awarded because the speech in question may have an adverse emotional impact on the audience. See NAACP v. Claiborne Hardware Co., 458 U.S. 886, 910 (1982) ("Speech does not lose its protected character . . . simply because it may embarrass others or coerce them into action"). And, as we stated in FCC v. Pacifica Foundation, 438 U.S. 726 (1978):
[T]he fact that society may find speech offensive is not a sufficient reason for suppressing it. Indeed, if it is the speaker's opinion that gives offense, that consequence is a reason for according it constitutional protection. [p56] For it is a central tenet of the First Amendment that the government must remain neutral in the marketplace of ideas.
Id. at 745-746. See also Street v. New York, 394 U.S. 576, 592 (1969) ("It is firmly settled that . . . the public expression of ideas may not be prohibited merely because the ideas are themselves offensive to some of their hearers").
And the Court concluded:
We conclude that public figures and public officials may not recover for the tort of intentional infliction of emotional distress by reason of publications such as the one here at issue without showing, in addition, that the publication contains a false statement of fact which was made with "actual malice," i.e., with knowledge that the statement was false or with reckless disregard as to whether or not it was true. This is not merely a "blind application" of the New York Times standard, see Time, Inc. v. Hill, 385 U.S. 374, 390 (1967); it reflects our considered judgment that such a standard is necessary to give adequate "breathing space" to the freedoms protected by the First Amendment. [p57]
Hustler Magazine, Inc. v. Falwell
While defamation (in this case libel) was lost from the start and never heard at the Supremies level, this is the rule and the rationale that has followed for public figures in cases of this nature. It's actually a restatement and clarification of an older statement of the rule, from
New York Times v. Sullivan.
So "harm" is not enough, not for a public figure. It's too subjective. Was there actual malice as defined here? That's the question.