Not often I agree with mgidm86 but he is right this time. Although it happens proportionately more to black people the problem with police in the USA isn't solely a racial one, it is a cops vs society one and if a cop feels even mildly distressed by a civilians actions whatever their colour you have the chance of a fatal outcome.
As to this shooter, does it matter if he was Nazi, Communist or Monster Raving Loony Party in his motivations? He clearly was someone who shouldn't be getting easy access to firearms yet here we are again.
Sadly for some it does seem to matter, everything has to be ascribed as either "for" or "against" their "side" so they can use the event as a weapon to win the fight.