Analysis of information sources in references of the Wikipedia article "Incorporation of the Bill of Rights" in English language version.
The Amendment governs only courts which sit under the authority of the United States, including courts in the territories and the District of Columbia, and does not apply generally to state courts.
For present purposes, we may and do assume that freedom of speech and of the press which are protected by the First Amendment from abridgment by Congress are among the fundamental personal rights and "liberties" protected by the due process clause of the Fourteenth Amendment from impairment by the States.