The Supreme Court defined public figures as those who "hold government office" and those "who have achieved a role of special prominence in the affairs of society by reason of notoriety of their achievements or vigor and success with which they seek the public's attention".
Since the First Amendment to the Constitution covers speech concerning public figures, the Court’s definition of "public figure" determines whether or not a plaintiff is a "public figure" in cases of defamation.
Private figures are individuals who have not sought out notoriety.
Because they have not sought notoriety, courts recognize that private individuals have not courted attention to or comment upon their actions.
Ergo, private persons are generally afforded a higher degree of protection and privacy.
https://scholar.google.com/scholar_...703896207&q=Green+v.+Rogers&hl=en&as_sdt=4,14