The hearing was about whether he should sue only the city of Fort Worth, or also sue the individual officers personally.
The law about that is the officer os personally liable for monetary damages only if *all* reasonable cops would know that what they did was unconstitutional, because there was clearly established law covering those specific actions in that particular circumstance. In all other cases, the offended party can sue the city or state that the cop works for.
A couple of examples:
A cop is interviewing a suspect. When the suspect just sits there, refusing to talk, the cop hits the suspect with a stick in an attempt to force a false confession. The officer would be personally liable because it's *clearly established* that such behavior is violates the suspect's Constitutional rights. No reasonable cop could think it's okay to hit the guy.
On the other hand:
Two weeks after a police station in Dallas is shot at, a guy is hiding in bushes across the street from a police station near Dallas. Cops approach to see what's going on. The guy is filming the police station (casing it?). Cops ask for ID. The guy asks to speak to a supervisor. The cops call their supervisor to come over, handcuffing the guy for five minutes until the supervisor arrives. Did they violate his Constitutional rights? Maybe. Does every reasonable officer *know* that what they did violates his civil rights? No, an officer might reasonably *think* it's okay to cuff the guy for five minutes. There's not *clearly established law* that in the situation described, they can't cuff him while awating the supervisor he requested. Therefore he can sue the city the cops work for, but can't sue the individual cops personally.
The second scenario above, in which a reasonable cop might mistakenly think cuffing him for a minute is okay, is patterned after the actual events in this case. In reality, he wasn't hiding in the bushes. I added that to make it a better example, an example of a scenario where a reasonable cop might be unsure of what they can and can't legally do.