Ernie
The definition of riot is 10 or more people acting together, unlawfully, with a common purpose in a given area.
An incident is not formally termed a riot unless absolutely necessary as under statute this bestows certain obligations on government (total cost of damage for instance). Below riot, you have violent disorder and the public order incidents. None of these have any link to whether or not a demonstration is going on.
There is no question that a riot took place that day. Hence your statement, assessing whether or not there was a riot from what you saw of it, is ridiculous. Unless of course you have some expertise in this area or were actually there.
Perhaps bring some facts to the table instead of left wing anti-police prejudices.