Others have pointed out that your links, which had no science, talked about police shootings. But the greater point is that shootings is a great proxy for lethal force, since knees-on-necks are fairly rare. And there is not difference in such force.
Somehow you missed the most important reason, which is the utterly broken inner city black culture. It's not about skin color -- Nigerians are the most successful immigrant class currently. Ethiopians do very well as well. We've discussed this before: it's about personal responsibility, commitment to education, and family values.