He's not. The hold in the picture happens to be "banned". That particular grab and hold happens to be deadly force. It is intended to knock someone out quickly, or kill them. The thug's presentation was not at all that of a trained cop either. He's a union thug.
We shall see. But if Russell sues, he should be able to find out the name of the guy.
Here's the coverage from the Cincy Enquirer:
http://www.enquirer.com/midday/09/09092004_News_mday_kerryprotest09.html