Sef Gonzales (born 16 September 1980) is a Filipino Australian who was convicted and sentenced in the Supreme Court of New South Wales to life imprisonment for the murder of his father Teddy Gonzales, aged 46 years, his mother Mary Loiva Josephine, aged 43 years, and his sister Clodine, aged 18 years. On 10 July 2001 at about 4:30 p.m., Gonzales entered Clodine’s bedroom in the house at 6 Collins Street, North Ryde, where she was studying. He was armed with a baseball bat or similar item and with two kitchen knives he had taken from a knife block in the kitchen. It was found that he compressed Clodine’s neck trying to strangle her, struck at least six separate blows to her head with the bat, and stabbed her many times with one or both of the knives. He inflicted five major stab wounds to Clodine’s neck and two major stab wounds to her chest or abdomen. The cause of Clodine’s death was the combined effect of the compression of her neck, the blunt force head injuries and the abdominal stab wounds.
Mary Loiva arrived home about 5:30 p.m. After entering the house, Sef attacked her with one of the kitchen knives in the living/dining room. Gonzales inflicted multiple stab wounds and cuts to her face, neck, chest and abdomen. Her windpipe was completely transected in the attack. Teddy arrived about 6.50pm. After entering the house, Sef attacked him with one of the kitchen knives and inflicted multiple stab wounds to his neck, chest, back and abdomen. One of the stab wounds penetrated his right lung, another penetrated his heart and another partially severed his spinal cord. Teddy sustained defensive wounds, suggesting that there was a struggle.
After killing his family, Gonzales disposed of the murder weapons, including the bat he had used in striking Clodine, and the shoes and clothing he was wearing at the time of the murders, which had become blood stained. He showered, changed clothes, and at some time during the evening, spray painted the words "Fuck off Asians" on a wall in the house in an attempt to fool investigating police into believing that his family had been the victims of a hate crime. Gonzales' clothes were later found to have the same paint used in the graffiti scrawl.