If this account is correct, how is he charged with simple battery as opposed to aggravated or second degree battery?
Because he used his fists. Under Louisiana law . . . Simple battery is defined as the “intentional use of force or violence” on someone else. It is a misdemeanor offense and carries up to 6 months in jail and fines reaching $1,000. Second Degree Battery is defined as committing a battery where intentional serious bodily injury is inflicted. This includes injury which features unconsciousness, extreme pain, disfigurement, loss or impairment, or substantial risk of death. A felony offense, second degree battery is punishable by up to 5 years in prison and fines reaching $2,000. Aggravated Battery is more serious than simple battery and is defined as a battery where a dangerous weapon is used. This is a felony offense that carries up to 10 years in prison and fines reaching $5,000. Aggravated Second Degree Battery involves aggravated battery as defined above (inflicting serious injury) and the use of a dangerous weapon. This is one of the most serious of violent crimes under Louisiana law and carries up to 15 years in prison and fines reaching $10,000.