while you saw a 'criminal in police custody' who hadn't yet been determined to actually BE a criminal - i saw a man, completely subdued;
And yet you and your comrades celebrate the arrests of these officers involved before it's proven they had anything to do with the death of this career criminal. What you saw was only part of what happened. If you don't cooperate with police, they cuff you. If you are cuffed and you're still out of control, they restrain you.
The guy was passing around counterfeit money. Did you ever see a cashier use a marker put a slash on 20 or 100 dollar bills in the store? Why do you think they do that? It isn't for art. Those pens indicate counterfeit bills. It's all the proof you need to make an arrest.