If you read the report that explains in great detail what happened (as opposed to just saying 'well, there's no smoke without fire') - you will see what I mean: http://www.nytimes.com/interactive/2014/08/13/us/ferguson-mi...
Eric Gardner was indeed a completely different case. His death was an unfortunate accident. The cop did not intend to kill him - he was looking for a way to subdue a very large man. I do agree that under normal circumstances it should be treated as manslaughter (ie unintended killing).
2. Your scenario is missing a very important point. I'm not saying that black arrest rates are much higher, hence this proves criminality.
Rather the rates for being convicted for serious crimes (like murder) is off the charts. Likewise victim reports of the race of crime perpetrators matches the conviction stats.
So basically the innocent black guys who just smoked weed in a car and happened to be pulled over because they're black are not going to jail for it (maybe a fine at most).
2. So let's say a white person and a black person in a car have the same rate of performing a crime (let's say smoking marijuana, a harmless pastime enjoyed by all races). Let's say that if a cop pulls you over while you are smoking marijuana, then you will be arrested. Well if a cop is twice as likely to pull you over if you are black, then there will be twice as many black arrests. This is a simplistic model and doesn't even factor situations where a black person gets pulled over, and definitely gets forced out of his car, handcuffed, and searched, whereas a white person might be able to cordially get away with a smile and a "Yessir".