"Congress shall make no law respecting an establishment of religion,
or prohibiting the free exercise thereof;
or abridging the freedom of speech, or of the press;
or the right of the people peaceably to assemble,
and to petition the Government for a redress of grievances."
As for Freedom of speech:
"The Free Speech Clause went through several iterations before it was adopted as part of the First Amendment. James Madison drafted an initial version of the speech and press clauses that was introduced in the House of Representatives on June 8, 1789. Madison’s draft provided: The people shall not be deprived or abridged of their right to speak, to write, or to publish their sentiments; and the freedom of the press, as one of the great bulwarks of liberty, shall be inviolable.1 The House of Representatives special committee rewrote Madison’s language to make the speech and press clauses read: The freedom of speech and of the press, and the right of the people peaceably to assemble and consult for their common good, and to apply to the government for redress of grievances, shall not be infringed.2 The Senate subsequently rewrote the speech and press clauses to read: That Congress shall make no law abridging the freedom of speech, or of the press, or the right of the people peaceably to assemble and consult for their common good, and to petition the government for a redress of grievances.3 Later, the Senate combined the religion clauses and the speech and press clauses4 and the House and Senate agreed to final language in conference.
There was relatively little debate over the speech and press clauses in the House, and there is no record of debate over the clauses in the Senate.5 During debate over the clauses, Madison warned against the dangers that would arise from discussing and proposing abstract propositions, of which the judgment may not be convinced. I venture to say, that if we confine ourselves to an enumeration of simple, acknowledged principles, the ratification will meet with but little difficulty.6 The general statement of these simple principles, however, gave rise to controversy when applied to specific government actions.7
The Sedition Act of 1798 sparked one such controversy that crystallized a national awareness of the central meaning of the First Amendment.8 The law punished anyone who would write, print, utter or publish . . . any false, scandalous and malicious writing or writings against the government of the United States, or either house of the Congress of the United States, or the President of the United States, with intent to defame . . . or to bring them . . . into contempt or disrepute.9 While Thomas Jefferson and Madison condemned the act as unconstitutional, the Adams Administration used it to prosecute its political opponents.10 Although the Supreme Court never ruled the Sedition Act unconstitutional prior to its expiration in 1801, the Court later recognized a broad consensus from the political and judicial branches that the act was unconstitutional.11
"The overbreadth doctrine focuses on the need for precision in drafting a statute that may affect First Amendment rights, and more concretely, allows a special kind of facial challenge to statutes.1 Ordinarily, to prevail in a facial challenge—a claim challenging a statute on its face, rather than only in certain applications—a litigant must ‘establish that no set of circumstances exists under which the [law] would be valid,’ or show that the law lacks ‘a plainly legitimate sweep.’2 Accordingly, if a statute sweeps in both protected and unprotected activity, the Court will ordinarily only invalidate its application to protected conduct.3 In the context of the First Amendment, however, the Supreme Court has allowed a person whose own conduct may not be constitutionally protected to bring a facial challenge to a law, if the statute is so broadly written that it sweeps in protected speech and could therefore have a deterrent effect on free expression.4 The overbreadth doctrine thus allows the facial invalidation of a law that punishes a ‘substantial’ amount of protected free speech, ‘judged in relation to the statute’s plainly legitimate sweep.’5 For example, in United States v. Stevens, the Supreme Court applied the overbreadth doctrine to rule unconstitutional a federal law that criminalize[d] the commercial creation, sale, or possession of certain depictions of animal cruelty.6 The Court described the statute as a criminal prohibition of alarming breadth, and concluded that the presumptively impermissible applications of [the law] . . . far outnumber any permissible ones.7
The Supreme Court has recognized, however, that there are substantial social costs created by the overbreadth doctrine when it blocks application of a law to constitutionally unprotected speech, or especially to constitutionally unprotected conduct.8 The Supreme Court has cautioned that facial [i]nvalidation for overbreadth is ‘strong medicine’ that is not to be ‘casually employed.’9 The requirement that a law must be substantially overbroad accounts for this concern.10 In addition, the Supreme Court has said a state statute should not be deemed facially invalid unless it is not readily subject to a narrowing construction by the state courts, and its deterrent effect on legitimate expression is both real and substantial.11 Further, the Court has said that overbreadth analysis does not normally apply to commercial speech.12"
Link: It's lengthy but maybe you'll read it