A "constitution" typically is a document which states the fundamental political principles of a governing body. The Constitution of the United Federation of Planets is such a document and contains at least twelve "Guarantees" related to fundamental individual rights of citizens. The Seventh Guarantee against self-incrimination during legal proceedings was considered by Captain Picard in 2367 as "one of the most important rights granted by the Federation." In some instances those protections related to fundamental rights can be extended to non-citizens while on Federation territory (such as a Starfleet vessel).
The Twelfth Guarantee of the Constitution dealt with the rights of artists, and defined an artist as "a person who creates an original artistic work"