I read in the AJC that the officer is not trying to tell a different story.
Turns out that according to him, he was wearing his uniform and told the guy to not cross the street at that spot BEFORE he crossed....the guy told him "thanks for the advice" (because according to the guy he didn't know the guy was a policeman) and walked across anyway....the cop then grabbed him and started questioning him....the guy still didn't believe he was a cop.....so the cop tells him he's under arrest and he throws the guy to the ground and calls for backup.....when back up arrives, the guy says (and is quoted as such even in the cop's own report) "now I believe you're a cop..."
Now the part that I don't get is this: IF the cop was in fact wearing his uniform, why would the guy say what he said? The cop even quoted him saying that, which is not too good for him IMO.
It's crazy. I still think he over did it. A ticket maybe. An arrest though??? That's crazy.