In the United States, the First Amendment protects the right to free speech, which includes the right to express opinions and ideas about an individual without government interference: 

• Truthful or based on an honest opinion

Generally, a person cannot be held liable for what they say or write about another person if it's truthful or based on an honest opinion. 

• Protects offensive speech

The First Amendment protects speech that many would consider offensive, hateful, or harassing. 

• Does not protect false statements

The First Amendment does not protect false statements about an individual that harm their reputation or expose them to hatred, contempt, or embarrassment. 

• Protects other mediums of expression

The right to free speech includes other mediums of expression, such as what a person wears, reads, performs, or protests. 

Defamation is any false information that harms the reputation of a person, business, or organization. Defamation includes both libel and slander. Libel generally refers to defamatory statements that are published or broadcast (more permanent) while slander refers to verbal defamatory statements (more fleeting).