The First Amendment to the United States Constitution provides that Congress shall make no law abridging (curtailing) the freedom of speech. Thus, free speech is only protected by the U.S. Constitution when it is the government that seeks to limit free speech. The First Amendment is inapplicable when a nongovernmental person or entity—such as a private business—seeks to limit free speech.

And some types of speech are afforded more protection than others. For example, commercial speech—speech that proposes a commercial transaction—is entitled to First Amendment protection, but less protection than political speech.

In the 1980 case Central Hudson Gas & Electric Corp. v. Public Service Commission, the U.S. Supreme Court developed a four-part test to determine whether commercial speech regulation violates the First Amendment:

1. Whether the commercial speech concerns a lawful activity and is not misleading;

2. Whether the government interest asserted to justify the regulation is "substantial";

3. Whether the regulation "directly advances" that government interest;

4. Whether the regulation is no more extensive than necessary to serve that interest.

In New Jersey, as in all states, the First Amendment to the United States Constitution protects freedom of speech from government infringement but does not apply to private entities. This means that while the government cannot unduly restrict an individual's speech, private businesses and persons are not bound by the First Amendment in the same way and can set their own rules regarding speech on their property or platforms. When it comes to commercial speech, which includes advertising and other speech proposing a commercial transaction, it is protected under the First Amendment but to a lesser degree than political speech. The Central Hudson Gas & Electric Corp. v. Public Service Commission case established a four-part test to assess the constitutionality of commercial speech regulations. This test is used to ensure that any government regulation of commercial speech in New Jersey is justified by a substantial interest, directly advances that interest, and is not more extensive than necessary. An attorney advising on matters of speech regulation in New Jersey would consider both federal constitutional principles and any relevant state statutes that may further regulate or protect speech.