No, but when police officers in the US are eight times more likely to kill an unarmed black person than a white person, it's a conclusion to be considered.
When per capita, a person of colour is three times more likely to be arrested than a white person for the same crime, it's a conclusion to be considered.
When a person of colour is likely to receive nearly three times the length of custodial sentence than a white person, it's a conclusion to be considered.
We could also talk about the disproportionate numbers of people of colour in prisons, on death row and those proven to have suffered a miscarriage of justice.
There is no proof that the individual officer(s) acted due to his race, but statistically the evidence would suggest it's likely it may have - consciously or not.
In terms of the last one, until race isn't an issue (as proven by the statistics) it definitely should be brought up. It may not always be the factor in a case...
... but as a whole it is. So back to my original point, maybe if black people weren't more likely to be killed when unarmed it wouldn't need to be brought up.
Cause and effect - deal with the root issue rather than trying to blame those who are facing the injustice.