The First Amendment issue here is, as the parties frame it, fairly narrow: is there a constitutionally protected right to videotape police carrying out their duties in public? Basic First Amendment principles, along with case law from this and other circuits, answer that question unambiguously in the affirmative.
The filming of government officials engaged in their duties in a public place, including police officers performing their responsibilities, fits comfortably within these principles. Gathering information about government officials in a form that can readily be disseminated to others serves a cardinal First Amendment interest in protecting and promoting “the free discussion of governmental affairs.” ... This is particularly true of law enforcement officials, who are granted substantial discretion that may be misused to deprive individuals of their liberties.
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Ensuring the public's right to gather information about their officials not only aids in the uncovering of abuses, see id. at 1034–35 (recognizing a core First Amendment interest in “the dissemination of information relating to alleged governmental misconduct”), but also may have a salutary effect on the functioning of government more generally, see Press–Enter. Co. v. Superior Court, 478 U.S. 1, 8 (1986) (noting that “many governmental processes operate best under public scrutiny”).
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Such peaceful recording of an arrest in a public space that does not interfere with the police officers' performance of their duties is not reasonably subject to limitation.
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In our society, police officers are expected to endure significant burdens caused by citizens' exercise of their First Amendment rights. ... The same restraint demanded of law enforcement officers in the face of “provocative and challenging” speech, id. at 461 (quoting Terminiello v. Chicago, 337 U.S. 1, 4 (1949)), must be expected when they are merely the subject of videotaping that memorializes, without impairing, their work in public spaces.