But in case you find the search feature less than helpful, as I often do.
It's still being fought out in the courts. So far most the rulings are that you do have the right to film, but in some cases it depends on where you are. Utah is pretty safe. Most the real attempts to punish filmers come in two party consent states, where they try to associate it with recording a private conversation.
As to the actual interaction with the police. The SCOTUS has said that you do have to give your name, but you do not have to provide ID if you are not driving, unless you are a legal resident alien, when you must always have your green card and present it when asked, (unless you are an illegal then that is somehow racist). And as always, other than giving your name, you have the right to remain silent. The problem is to many don't have the intelligence or ability to remain silent.
As to the video. They are within their rights but I don't really care for chip-marchers. Those who go out looking for negative contact just to have something to film. That was obvious by the constant change in their messages. Sure the signs remained the same, but 9/11 conspiracy, dressing like a prisoner? What do either of those have to do with their purported message? What they were really doing was trying to find messages designed to draw attention.
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