40 U.S.C. § 6134 : US Code - Section 6134: Firearms, fireworks, speeches, and objectionable language in the Supreme Court Building and grounds

      It is unlawful to discharge a firearm, firework or explosive, set
    fire to a combustible, make a harangue or oration, or utter loud,
    threatening, or abusive language in the Supreme Court Building or
    grounds.