Atlanta PD has a history of citizen abuse going back many years.

The arresting cop apparently has "other issues" besides this incident...
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APD spokesman Lt. Curtis Davenport said Dolson is "suspended without pay for an unrelated incident."
So, he may have a 'history'.

And, the woman was doing nothing illegal, so the cop had no reason to order her to move.

And, yes, he owed her a reason for the order. This is not Nazi Germany where the citizens have to snap to attention or else.

"The time for war has not yet come, but it will come and that soon, and when it does come, my advice is to draw the sword and throw away the scabbard." Gen. T.J. Jackson, March 1861