Fighting Words
Government may prohibit the use of “fighting words,” which is speech that is used to inflame another and that will likely incite physical retaliation. Likewise, language that is meant to incite the masses toward lawless action is not protected. This can include speech that is intended to incite violence or to encourage the audience to commit illegal acts. The test for fighting words is whether an average citizen would view the language as being inherently likely to provoke a violent response.

Obscenity
Most forms of obscenity are protected by the First Amendment. However, there is a high threshold that must be met in order for obscenity not to be protected, which includes showing that the language appeals to the prurient interest in sex, that it depicts something that is considered patently offensive based on contemporary community standards and that it lacks serious literary, scientific or artistic value.

Child Pornography
Child pornography is an exception to the First Amendment’s right to free speech and to having to meet the high threshold test for other obscene works. Speech is not protected if it depicts a minor performing sexual acts or showing their private parts.

Libel and Slander
The First Amendment does not protect individuals from facing civil penalties if they defame another person through written or verbal communication.

Crimes Involving Speech
The First Amendment also does not provide protection for forms of speech that are used to commit a crime, such as perjury, extortion or harassment.

Threats
Speech is not usually protected when it constitutes a threat toward another that places the target of such speech of bodily harm or death. There are certain exceptions, such as when a reasonable person would understand the language not to be a credible threat. Additionally, threats of mere social ostracism or boycotts are protected by the constitution.

Violation of Copyright Rules
Intellectual property is protected, including copyrights and trademarks. The Supreme Court has held that copyright laws can withstand a First Amendment challenge based on the freedom of speech.

Conduct Regulations
The government is permitted to make laws regarding the conduct related to speech, such as by stating when speech may be provided, where it may be provided and how it can be communicated. Courts generally uphold these types of regulations as long as they are considered content-neutral and not directed only at prohibiting the expression of certain ideas. For example, the government may prohibit demonstrations at certain locations, may limit the size of a poster used for speech and may limit the amount of sound that can be heard at specific times.

Commercial Speech
While commercial speech is protected, it is generally viewed as having “diminished protection.” Commercial speech may be faced with many more regulations than speech from a private citizen if a substantial government interest is advanced and the government’s restriction is no more extensive than necessary. This type of protection serves the interest of protecting the public from false information while still recognizing the need for free communication between businesses and potential customers.