This two-tier approach retains importance for those who believe that carefully crafted controls over certain categories of speech (such as pornography, commercial advertising, or abusive epithets) do not violate First Amendment guarantees. Although the Court continues to cite Chaplinsky's position on “fighting words” approvingly, subsequent cases have largely eroded its initial, broad formulation; libelous publications and even verbal challenges to police officers have come to enjoy some constitutional protection. Chaplinsky remains the last case in which the Court explicitly upheld a conviction only for “fighting words” directed at public officials.