Chronology of Brown's Attack on Officer Wilson:
1. Brown and accomplice rob store and batter store clerk.
2. Officer Wilson attempts to stop Brown on street for interview.
3. Brown attacks officer, tries to wrestle away his gun, and strikes him in the face, breaking officer's eye socket.
4. Officer's vision is impaired by injuries caused by Brown. Blood and sweat in eyes further limit vision.
5. 300 pound Brown continues to attack visually impaired officer.
6. Officer, fearing death or great bodily harm, uses only means available (his gun) to defend himself.
7. Most of the shots aimed at Brown strike Brown in the arm due to officer's visual impairment caused by Brown's attack.
8. Attacker Brown finally neutralized. Officer Wilson survives attack.