This footage shows cops arresting a bystander after the man filmed a traffic stop in Killeen, Texas. The cop concedes at one point that the man has the right to film, but claims that the man speaking to the occupants of the vehicle interfered with the investigation.
Texas's interference statute begs to differ:
(d) It is a defense to prosecution under this section that the interruption, disruption, impediment, or interference alleged consisted of speech only.
The cop was obviously just upset that the man informed the passengers of their legal right not to talk to cops. That's the deal with this particular instance of police misconduct, at least until the city's insurer pays out to avoid a lawsuit