aha, it’s because the rally is over. braynard is warning people to leave peacefully and stay in groups. i guess the cops are anxious about the transition - this crowd will leave the fenced in permitted area and pass a small number of counter protesters across the street.
there seems to be no rhyme or reason for the way the cops keep marching by and reforming their line in front of the capitol reflecting pool. it honestly just seems like they know it makes for a striking photograph - the police protecting the capitol this time.