On the streets of San Francisco. Were calling on an immediate independent investigation. Reporter one of the officers involved made news in 2009 when he was caught on camera saying he would break your arm like a twig. Reporter if you resisted arrest. The texts were the latest in a string of embarrassment of the department. This video of police trying to stop an African American man in a wheelchair from intervening in a police stop at the sunnydale projects. In my 21 years i can assure you its not. We have to review at least 100 cases and probably more. Every case where these officers testified in racial bias may be an issue. Reporter the District Attorney George Gascon announced he is going to be reviewing cases as well. The officers for justice which represents black police say it may go further and warrant even further investigation. Phil matier in San Francisco. We just learned the District Attorney will not file charges against one of the suspects in the murder of an oakland mother