Final answer:
Chief Justice Rehnquist differentiated the legal implications between stating an opinion versus stating a fact when it comes to defamation law, with a focus on the protection of free speech under the First Amendment, especially for public figures as established by the Supreme Court.
Step-by-step explanation:
Chief Justice Rehnquist's opinion in Milkovich v. Lorain Journal compared the statements "In my opinion Mayor Jones is a liar" and "In my opinion Mayor Jones shows his abysmal ignorance by accepting the teachings of Marx and Lenin." Rehnquist suggests a difference in the legal implications of these statements, relating to defamation law and the protection under the First Amendment of opinion versus factual assertion. He specifically addresses how the expression of an opinion, which does not assert or imply a false statement of fact, is protected under the free speech clause.
In defamation cases like New York Times v. Sullivan, the Supreme Court established higher standards for public figures to claim defamation, requiring proof of malice or reckless disregard for the truth. These standards protect critics from being silenced through fear of lawsuits. However, just stating it is an opinion does not categorically immunize a speaker from defamation if the statement implies undisclosed facts which can be proven true or false.
Statements like "In my opinion Mayor Jones is a liar" may imply a knowledge of undisclosed facts, thus not purely being opinion whereas stating someone's alleged ignorance due to acceptance of certain teachings may be seen more as a subjective viewpoint, which tends to be protected. This differentiation is crucial in the balance between protecting reputation and upholding free speech rights.