What evidence do you have other that what you heard in the news? Wait for it.
Evidence of what? Not sure what you mean, but we take a reasonable interpretation of our observations. Extraordinary interpretations are the ones that require evidence other than what is normal and customary and reasonable.
This particular incident, if actually happened as reported, is sad. The police were tasked with clearing the area, due notice was given to disperse. The man confronted the cops as they they moved their line forward to clear the area.
You can spin the actual physical confrontation if you wish, but the cop was not trying to injure the man, only trying to push him back.
How did I spin it. I said what happened.
Even if you aren't trying to injure someone, you may still be liable for the injuries you cause.
The guy falls awkwardly back....
Yeah, he fell back like a typical old man would fall when suddenly push by a physically fit, young police officer.
The force was excessive.
If the old man was breaking the law, arrest him. If an officer decides to relocate another human without their consent, then they should take responsibility for their safety in doing so.
If the man did as ordered would it have happened?
Assuming he was ordered to back up, no.
If they had only arrested him for disobeying a "lawful" order, would it have happened?