Congress shall make no law . . . abridging . . . the right of the people peaceably to assemble, and to petition government for a redress of grievances.
The rights of peaceable assembly and petitioning the government tend to get obscured by the more familiar 1st Amendment rights of free speech and religion. The Assembly and Petition Clauses have rarely been controversial. Indeed, the only real debate they occasioned during their framing and ratification was whether or not they were really necessary in light of the protection of free speech.
Like many other rights listed in the first ten amendments, the meaning of the Petition and Assembly Clauses has expanded over the years. They now apply to state as well as federal laws, and the original right to assemble for political purposes has expanded into a broad category of “expressive association.”