Speaking about freedom of speech, it is important to distinguish two things: facts and judgments.
Facts are events that took place in reality.
Perceptions are the subjective opinion of an individual about a particular phenomenon.
Freedom of speech is to have the right to express one's perceptions, but to have an obligation to prove facts.
For example, any person can say that he does not like some other person or that he considers someone to be smart, stupid, good, bad, etc.
But no one can baselessly call another person a criminal, a thief, a murderer, because these statements are about the fact and require proof.