I had this same question and I was just looking for the answer. I believe it is true, In my civics book I found details showing that Thomas Jefferson added the bill of rights because he said that "a bill of rights is what people are entitled to and what no just government should refuse."
I believe the answer is: <span>American Values and American racial policies
American racial policies in the past often discriminated against the minorities while giving a lot of space to the race majority. (such as the segregation law)
This lead to the situation where it became really difficult for members of racial minorities to advance in American soicety.</span>
Their profession and skill in their profession
Print posters and campaign materials