 The First Amendment to the United States Constitution prohibits states from enacting laws that abridge the freedom of speech . Municipal governments may not " restrict expression because of its message , its ideas , its subject matter , or its content " . Laws that regulate speech based on the expressive content of the speech are presumptively unconstitutional ; such restrictions are only permissible when they are narrowly tailored to serve a compelling state interest . For the purposes of the First Amendment , government regulation of speech is considered " content @-@ based " when it targets speech because of ideas or messages that are expressed . Furthermore , some laws may still be considered " content @-@ based " even though they appear to be facially content @-@ neutral . Laws are considered " content @-@ based " if they cannot be " justified without reference to the content of the regulated speech " or if they were adopted " because of disagreement with the message [ the speech ] conveys " . 
