Generally, only content-based restrictions on speech are subject to strict scrutiny under the First Amendment, whereas "time, place, and manner" restrictions (e

Generally, only content-based restrictions on speech are subject to strict scrutiny under the First Amendment, whereas "time, place, and manner" restrictions (e.g., noise ordinances) are more tolerated. Additionally, commercial advertising is less protected than other speech under the First Amendment. Laws against spam do not target messages on the basis of their content (except in so far as they are commercial advertising, which is a less protected category of speech), so they are upheld as a "time, place, and manner" restriction.