If they live in the United States they have a right to use the state to prohibit it. The First Amendment guarantees the right to petition the government for redress of grievances (whether real or perceived).

In the words of the Copley First Amendment Center, "People have the right to appeal to government in favor of or against policies that affect them or in which they feel strongly. This freedom includes the right to gather signatures in support of a cause and to lobby legislative bodies for or against legislation"