It is an attack on liberty by police when they claim that you're going to be arrested for cross the street safely with a crossing flag.
But that isn't what happened in the video. When the cameraman/cop watcher crossed the street with the flag he was not bothered in anyway by the officers, whom he clearly knew, and it they knew him. The officers said nothing to him, and made no threat to arrest him. But then after crossing the street, and as the undercover cop now went to continue his operation, the cameraman with a flag decided to follow after the cop in the crosswalk, with a flag, thus impeding what the officers were attempting to enforce. Which was drivers failing to yield for pedestrians, even ones not using the crossing flags.
At that point the cop-watcher is in danger of being in violation of interfering, but maybe not yet. What happens next is the police warn the copwatcher that if he continues he will be arrested. A warning is given, and a clear explanation to the citizen that the police are conducting and OPERATION and then his presence in the same manner which he is doing WILL BE considered interference. And you know what, the cop watcher asshole knows enough about the law, that despite his childless attempt to bait the officers, the copwatcher asshole stopped what he was doing because he KNOWS the law is not on his side in that situation and he WILL BE arrested if he continues.
Him crossing the street was not a violation
Him crossing with the officers with a flag while clearly an attempt to annoy was not yet breaking the law
Any continued action AFTER receiving a clear warning (one which will stand up in court) would be the point where the law was violated.
What amazes me about this incident with some of you, that what the police are doing there is clearly in the public interest for safety. I don't see this as any infringement on citizen rights whatsoever. Keeping pedestrians safe....well, I would appreciate that kind of enforcement operation in my neighborhood, especially as I am the kind of driver who already yields to pedestrians, whether there is a crosswalk or not, or even where the pedestrian is in the wrong. Who wants to run anyone over? I don't.
Pedestrians ALWAYS have the right of way, even when they are wrong they must be yielded to, and that is the law in most states.