A more thorough explanation:

Viewpoint discrimination is when the government or an authority targets certain views or opinions expressed by speakers, rather than the subject matter itself. This is a type of content-based discrimination, where the government discriminates based on the content of a communication.

For example, if a government agency holds a workshop to inform state employees of laws related to the agency's functions, it may reasonably prohibit the expression of opinions regarding the motives of the legislators. However, if speech favorable to the legislators' intent is allowed and opponents are denied the opportunity to respond, the restriction would constitute viewpoint discrimination.

Another example of viewpoint discrimination is when a university denies funding to a student group because of their political views, while funding other groups with different views. This violates the First Amendment's protection of free speech and expression.

Viewpoint discrimination is not allowed under the Constitution, as it violates the principle of free speech and expression. It is important to protect the right to express different opinions and ideas, even if they are unpopular or controversial.