First-degree intentional homicide charges have been filed against a 25-year-old Oak Creek man who is accused of shooting his mother to death and fracturing his brother’s skull.  Police say Kervin Pierce called 9-1-1 Tuesday and admitted he had attacked his family members because he felt they had disrespected him.  Investigators say they recovered a broken handgun and a blood-covered knife from the home.  Pierce told police he tried to shoot his brother, too, but the gun jammed, so he beat the brother until the gun broke in half.  Pierce is also charged with attacking a correctional officer at the Milwaukee County Jail the day after his arrest.