I don't think you can inflate the problem of racism in America. It is good that people come to know about the real prejudices, especially towards black people, who were brought here forcefully.
There is some possible justification of racism towards Indians, Chinese, etc. because they are coming to America on their own accord and taking away American jobs. But, there is no justification for treating black people unfairly.
Some people are saying in the other answers that even black witnesses were supporting the account of the police officer. So what? Even his own testimony in the court sounded awful. Even in his own words, I could not find a single statement that justified the killing of a human being.