'Suicide' case turns to murder A DRUG dealer and his brother allegedly bashed the teenage daughter of a policeman before wrapping an electrical cord around her neck and hanging her from a rafter, an inquest has been told. The death of 15-year-old Leanne Melissa Thompson in September 2006, when she was in the care of Queensland's Child Safety Department, is being investigated as a potential murder -- after previously being treated as a suspected assisted suicide. But a key issue confronting coroner John Lock at this week's inquest is whether to accept as credible the startling evidence of Linda Hazel Hart, the brothers' neighbour, who told police in July 2010 she had witnessed the alleged murder, despite never saying so before. In 2011, an investigation by The Australian into Leanne's death exposed a litany of failures by Queensland's child protection system -- an issue into which Mr Lock will also delve. Alexander George O'Sachy -- who had been charged with assisting his young lover's suicide -- and his brother, Daniel, will front Mr Lock today; both have previously denied involvement in Leanne's death. O'Sachy's assisted suicide trial in 2009 resulted in a hung jury and it was when police were delivering subpoenas for his retrial in 2010 that Ms Hart made her revelations. Police later dropped the assisting suicide charge and commenced a homicide investigation. Alexander O'Sachy was separately convicted of unlawful carnal knowledge for having sex with the underage girl. Daniel O'Sachy has previously told police he saw his brother punch Leanne in the back of the head and tell her to "go and kill yourself." Lead investigating officer John Mison yesterday told the inquest he believed Leanne's death was suspicious, but said there were several inconsistencies between Ms Hart's version of events and objective forensic evidence. The court was shown a video of Ms Hart telling Detective Sergeant Mison in 2010 she had seen a screaming altercation between the O'Sachy brothers and Leanne on September 7, 2006, under the brothers' home. She said she saw the men "attack" Leanne, punching her in the head, screaming at her she was a "slut," and laughing at her. Ms Hart said the girl was on her knees on the floor when Daniel O'Sachy wrapped a grey electrical cord around her upper chest. She said Leanne screamed: "God help me, please someone help me." Ms Hart said she then saw the cord wrapped around Leanne's neck, Alexander O'Sachy holding her feet and his brother pulling the rope over a beam, suspending Leanne so her feet were off the floor. She said she then left her house, telling police in 2010 she had felt guilty ever since that she did not call for help or intervene. Forensic pathologist Michael Burke said Leanne's body showed no sign of being beaten. Dr Burke also said the ligature marks around her neck showed the girl's feet did not leave the ground. He said her neck injuries were "extremely difficult" to reconcile with a "simple hanging," and he could not say whether she had been hanged or strangled.