Brighter days … Dianne and daughter Leanne Thompson in 1993. Strangely enough it was Leanne's father, Damian Rockett, a Queensland police sergeant, who first received word of Leanne's hanging while on duty. After the inquest, Rockett said he believed O'Sachy would never reveal what happened to his daughter that day. "I know Alex O'Sachy," he added. "I just feel sorry for the next woman that he associates with." Alexander George O'Sachy and Leanne had shared a house with his older brother, Daniel, and Daniel's then 10-year-old son. Over time, both Daniel and his son had rung police and the Queensland Department of Child Safety expressing concern for Leanne's well-being and urging that she be removed from O'Sachy's influence. After her death, Daniel and his son gave disturbing evidence of O'Sachy beating Leanne, taking her money and supplying her with drugs. Daniel, 42, still lives at the same house at Wishart in Brisbane's south, owned by his father. He told Good Weekend that Alex O'Sachy was a chronic drug addict who refused treatment and seemed to have a morbid influence on those around him. He says their wealthy parents - divorced acrimoniously in 1994 and both remarried - have been providing his brother with lawyers, houses and cars. Daniel also says they tried to stop him giving evidence about what happened on the day Leanne Thompson died, but he wanted to show his own son he was "doing the right thing". It was largely due to Daniel's evidence that O'Sachy was brought to trial in 2009 for assisting in Leanne's suicide, but the jury couldn't reach a verdict. Since Leanne's death, O'Sachy has formed relationships with other young women. In 2009, he pleaded guilty to stabbing and assaulting one of them, Lisa Palmos, and received a suspended jail sentence; in 2011, Lauren Howarth - who had alleged that O'Sachy had threatened to cut off her finger and set her alight - was found dead of an apparent drug overdose in the house they shared.

Trail of woe … Alex O'Sachy outside court in 2012. Credit:Channel Seven O'Sachy was also mixed up with the suicide of 14-year-old Andrew Anderson, who shot himself in the head while on the phone to his father, saying, "Goodbye, Dad." Andrew had a troubled background and was under a Child Protection Order issued by Queensland's Department of Child Safety when he died on July 25, 2005, two days after shooting himself. He spent the night before the shooting at O'Sachy's Wishart house, drinking and using drugs. At his inquest in 2009, evidence was given that O'Sachy had supplied the drugs. Daniel tells me his brother "introduced [Andrew] to needles" by injecting him with amphetamines (speed) that night. Family fall-out … Leanne's father Damian Rockett in 2010. Credit:Marissa Calligeros "When people come off speed they feel real shit and depressed," Daniel says. "I told my brother, 'You're an absolute dickhead!' And he goes, 'I know what I'm doing - it was just the right amount to give him.' And then the next day [Andrew] shot himself." It happened early in the afternoon at the home of Andrew's grandfather, who told the inquest that O'Sachy was with Andrew when he left the house that morning.

O'Sachy denied supplying the boy with drugs, or the gun he used, but refused to answer questions at the inquest, claiming he'd "lost his memory" of Andrew and the night prior to the shooting. A mother's sorrow … Rosina Mason-Parker with a picture of her daughter Lauren Howarth. Credit:Fairfaxsyndication.com One minute he’s normal, then he’ll go off on a tangent. he’ll pick up a shovel and try to attack you. Like Alex O'Sachy's parents, Leanne's mother and father underwent a calamitous separation in 2002 that left Damian Rockett estranged from his two children. His ex-wife, Dianne Thompson, is convinced that Leanne was murdered; Rockett thinks she took her own life. Throughout her inquest they sat on opposite sides of the courtroom and didn't exchange a word. Strangely - although he knew of O'Sachy's brutality towards his daughter, and had tried to get her away from him - Rockett personally invited Alex and Daniel O'Sachy to Leanne's funeral.

Sad end … Lauren Howarth before she met Alex O'Sachy. Why would he do that? "Well," he says in his mild-mannered way, "he [Alex] had feelings for her, too. And Daniel and Alex both had to get her down when she was found hanging ... and I thought, 'Well, they need closure, too.' " Only a few days before the funeral, Dianne Thompson read a note allegedly written by O'Sachy to Leanne, and later presented at his trial, that began: "I'll rape ya and kill ya ..." Thompson was furious when she saw O'Sachy outside Leanne's church service, telling those with her, "How dare he be here!" Although both have remarried, the ill will between Leanne's parents hasn't diminished. Thompson tells me Rockett assaulted her "all through" their 20-year marriage; he says he punched her "only once" in the heat of the moment. This led to a police misconduct charge, and the issuing of a domestic violence order (DVO)against him. He says that by the end of the marriage she was threatening him with knives, and he took to sleeping in another bedroom with the bed wedged against the door.

Thompson says she told her husband to leave frequently, but he appealed to their weeping children, saying, "Mummy won't let me stay! Get Mummy to let me stay!" Rockett says the first time he tried to leave, she told the children, "Your father's leaving you for a slut." He adds,"Whenever I tried to leave after that she would attempt suicide by taking drug overdoses." About the only thing they agree on is that what happened between them had a dire effect on their kids (Leanne's brother Christopher, 25, still refuses all contact with his father). "Leanne used to be 'Daddy's perfect little girl', " Thompson tells me at what was once the Rockett family home at Belmont in Brisbane's east. "But [after he left] she told me she hated him. She said, 'Don't you dare ever take him back.' " At his home on the other side of the city, Rockett says he saw little of the children after the separation because his access was limited by the DVO. Leanne was a striking, vivacious girl who loved sports and dancing and wanted to be a fashion designer or a hairdresser. But from the age of 13 she began wagging school and staying overnight with "friends". Her absences from her mother's home grew longer, and Rockett and Thompson sought official help. In December 2005, Leanne was placed under a Child Protection Order issued by Child Safety. She was supposed to live at Brisbane's Phoenix House youth centre during the week and spend weekends with her mother. But she went missing from the youth centre for days at a time and insisted on spending weekends with friends she refused to identify to Thompson. In mid-2006, Rockett learnt that Leanne was living most of the time with Alex O'Sachy, well known in Rockett's own south Brisbane police district as a convicted drug dealer and "doctor shopper". By that stage, he says, Leanne was using drugs - including amphetamines and heroin - and had prostituted herself to pay for them. (Her mother angrily rejects this, saying Leanne was just a "bit wild" after having a taste of freedom.)

Rockett did his best to convince Child Safety that Leanne should be moved from O'Sachy's house. But, as the veteran cop already knew, the official line was that as long as Leanne visited her case worker three times a week, and a counsellor at Phoenix House, the department couldn't intervene. (Both O'Sachy and Leanne told police and Child Safety workers their relationship wasn't sexual, but DNA testing after her death showed it was.) Rockett was already familiar with Daniel O'Sachy, who was in the habit of ringing him or other police to report the presence of "vulnerable kids" at the Wishart house, or to tell "where the bongs were hidden". The box-like house where Leanne met her fate is drab and oppressive. Daniel and his son lived upstairs; Leanne and O'Sachy shared a room at the rear of the lower level. The only on-the-spot evidence of what happened there on Thursday, September 7, 2006, came in the form of police statements and court evidence from Daniel, who admits to being an alcoholic and a former heroin user, and his son, who was then underage and can't be named. As they tell it, O'Sachy and Leanne were up until after dawn, "fighting" over money in their room. Later in the morning Daniel saw Leanne mixing crushed Xanax (antidepressant) tablets in a spoon, while O'Sachy slept. She told him: "We are so f...ed up that I am doing morph." Daniel then went to the Child Safety office in nearby Mount Gravatt and told staff about the morphine and his concerns for Leanne. (No morphine was detected at her autopsy.) When he got home he saw O'Sachy punch Leanne in the back of the head, which was "not unusual". (Daniel tells me his brother punched Leanne there because "it didn't leave any marks".) About 2.45pm, while returning from a walk, Daniel and his son saw a dazed-looking Leanne stumbling about in traffic near their house. When she returned to the downstairs bedroom, O'Sachy told her, "Go and kill yourself." (Daniel tells me he heard his brother suggesting a suicide pact to Leanne that morning in which they would both jump off Brisbane's towering Gateway Bridge. She said, "But we don't have any money" - which Daniel took to mean money for a taxi to get to the bridge.)

O'Sachy then punched Leanne in the back of the head again, and Daniel called the police. At 3.44pm two uniformed cops arrived. They had a quick look around the house for Leanne, including downstairs, but couldn't find her and hurried off to check local streets. From upstairs, Daniel then heard O'Sachy call, "Oh, she has necked herself." He ran downstairs and saw Leanne hanging from a beam in a shadowy corner, her feet barely off the floor. He tried to lift her to get the electrical cord from around her neck, telling his brother, who was standing watching, "Hey, dickhead, give me a hand!" Together they got her down and took her to the front yard, where Daniel began CPR. His son called triple-0. Somehow, Daniel also found time to call Rockett, who that day was duty sergeant at the nearby Mount Gravatt police station. "He said, 'I know a little first aid, but can you get here quick - we've found her hanging underneath the house,' " Rockett recalls. "Apparently, she'd been there the whole time, and they hadn't seen her because she was [partly concealed by] a cupboard." Rockett had to man the radio and tell other police, "The 15-year-old girl has been found hanging under the house." In those impersonal terms? "Yeah, exactly," he says, staring at the floor.

He then called an officer at the scene who told him paramedics had restored Leanne's pulse, but she was still unconscious and her prospects weren't good. After that he called his second wife, arranged to collect her from work, and they drove together to the hospital where Leanne had been taken. "Do you think he bothered to tell me?" demands Dianne Thompson, shaking her head. "Damian didn't ring me, the police didn't ring me. It wasn't until 4.55pm that day that [a Child Safety employee] rang and said, 'I presume you've heard about Leanne?' I dropped the phone and started screaming ..." At the hospital, Thompson refused to sit in the same waiting room as Rockett and his wife. They each spent a short time at Leanne's bedside, but she didn't regain consciousness. At 11.58pm her life support was turned off and she was declared dead of hypoxic brain injury, due to hanging. At first, police treated it as a suicide. Rockett agreed, perhaps because Leanne had cut her wrists at his home in 2005, and the pattern of suicides within his own family. "My younger brother, Laurie, hung himself earlier this year," he volunteers. "My father's brother suicided in the late 1980s, and Dad's father jumped off a building and killed himself ... so the black dog [depression] has really been in our family." But in 2007, police changed course and charged O'Sachy with aiding in Leanne's suicide. Apart from the evidence from Daniel and his son, the charge was based on threatening notes from O'Sachy to Leanne found by Diane Thompson in her daughter's room, and statements from two of O'Sachy's other girlfriends, who said he'd admitted encouraging Leanne to kill herself. (Thompson says Rockett actively opposed her efforts to make a statement to police about the threatening notes, telling investigating police she was a "crazy f...ing bitch". It wasn't until she complained to police attached to the coroner's office that O'Sachy was charged with aiding Leanne's suicide.) After the jury failed to reach a verdict on this charge in 2010, startling new evidence was obtained from Linda Hart, the O'Sachys' next-door neighbour at the time of the tragedy. In 2006, Hart had told police only that she'd heard arguing and screaming from the house that day. But four years later she told, in harrowing detail, of having seen both Alex and Daniel beating Leanne and hanging her over the beam. This led to an 18-month murder investigation, but no charges eventuated.

Hart, who said she'd been harassed and threatened by the O'Sachy brothers for years, repeated her evidence at the inquest, but coroner Lock found it "most unlikely" she would've been able to see what she described from her window. Leanne's hanging occurred more than three hours after Hart claimed to see it (at a time when Hart wasn't home), and evidence from all three forensic pathologists contradicted Hart's description of what she saw. "It is difficult to understand why Ms Hart has given this version of events, which she appears to genuinely believe," Lock said. Of Daniel's alleged involvement, the coroner noted: "Father of the year he is not, but it would be most unlikely for him to bring to the attention of [authorities] his concerns about her welfare ... in the days and hours before her death, and then participate directly in her death." The trail of grief and misery involving Alex O'Sachy extends to a tiny flat in Brisbane's south, where Rosina Mason-Parker now lives alone. In 2011, a few months before her daughter Lauren Howarth was found dead of a suspected drug overdose in the house she shared with O'Sachy, Mason-Parker was asked by a TV reporter if she feared Lauren might die through associating with O'Sachy. "My answer was, 'Yes, yes, yes!' " she says now, covering her face. "And then it happened." (The TV interview didn't go to air.) Lauren, 31, lived with O'Sachy for almost a year while he was still being investigated over the death of Leanne Thompson. Her body was discovered by ambulance officers responding to a triple-0 call from an anonymous male on the morning of September 1. No one else was in the Birkdale house (another owned by O'Sachy's father, George), but police sources told Good Weekend that O'Sachy had admitted making the emergency call. An autopsy report indicates Lauren probably died from taking fentanyl, a prescription painkiller many times stronger than morphine.

Mason-Parker's "emotionally immature" daughter had moved from Sydney to live with her in an effort to beat her multiple drug addictions. She was on the methadone program, and her mother thinks she met O'Sachy while waiting in line at a local chemist. A few months after she moved in with him, Lauren began sending her mother phone texts alleging O'Sachy was beating and torturing her, taking her money and threatening her life. "It was an absolute house of horrors," Mason-Parker says. "Police have all the texts now, but Lauren would send messages like, 'He strung me upside down ... he stripped me naked ... he tried to strangle me by grabbing my windpipe ... he put objects in my private parts ... he tried to cut off my finger and [threatened to] set me alight with meths.' It was sadomasochism, or something, but no matter how hard we tried, the police and I couldn't get her away from him because he was supplying her with the drugs she needed." Mason-Parker says O'Sachy told Lauren repeatedly that she was "useless" and "worthless" and should kill herself. "And then she'd say to me, 'And I am, I am worthless, aren't I?' ... I only met O'Sachy once and he made my skin crawl. I have a strong [religious] faith, and I saw him as evil. When you were in his company you could feel it." Typically, O'Sachy refused to answer questions from police about Lauren's death. Last year, his father told journalists his son had nothing to do with it. "Alex was away," George O'Sachy said then. "She [Lauren] was there with two or three of her friends having a party that night ... if Alex had been involved he would've been charged." Mason-Parker scoffs, saying O'Sachy rarely let Lauren out of his sight: "He controlled her in every way." A coronial investigation into Lauren Howarth's death is continuing.

George O'sachy, 76, describes himself as a "former forensic investigator" and a "retired senior officer in the defence forces". His main concern these days seems to be in guarding his own reputation. "I don't want my name bandied about in the paper. That's the real issue," he says when I phone seeking a meeting. "I'm a respected person in this area, and I'm a practising Justice of the Peace in Victoria Point [on Brisbane's bayside]. I've got letters of appreciation from the Justice Department ..." The owner of a string of properties across Brisbane, the elder O'Sachy suggests the death of Leanne Thompson - "who was going to destruct herself anyway" - is an old story that has been "aired enough". What about Damian Rockett's expressed concern for other women Alex may associate with? "Well, Damian Rockett said to my former wife [Maria] that it was the best thing that could have happened to Leanne. He said that to her face. He said [Leanne] was better off where she is now. Because of her past, and her past history." (Rockett admits saying this to Maria when she delivered Leanne's clothing to him after her death. "Because there was only so much I could do," he reasons. "Leanne was too far gone." Dianne Thompson tells me the clothing wasn't even Leanne's: "She was a tiny size 8; these clothes were about size 14! I put them straight into a charity bin.") George O'Sachy decides not to meet with me. A couple of days later I speak with Daniel O'Sachy at the house where Leanne died. Thin and sallow with close-cropped hair, he tells how his grandparents on both sides of the family managed to escape Soviet Russia and find their way here during World War II. His parents were educated achievers (Maria became a GP and George an engineer), but the family was bitterly divided after they divorced in 1994, when Alex was 16 and Daniel was 22. Both brothers attended the prestigious Brisbane Boys' College, but after the "really ugly" breakup - when Alex and a younger brother stayed with Maria and Daniel lived with George - Alex went off the rails.

"Before that he was really good at school and at sports," says Daniel. "Then he started living in a tent in Mum's backyard and growing marijuana. He was selling drugs and taking heroin and speed. He stopped going to school, and got this really intense dislike of authority." Daniel says the enmity between their parents still affects all their lives. Alex, diagnosed as schizophrenic and on some sort of pension, had been abusing and "controlling" drug-addicted girls and running amok for years. "One minute he's normal, then he'll go off at a tangent," says Daniel. "He'll pick up a shovel or something and try to attack you ... once, he shoved a loaded handgun in my face." Daniel's son, now 17, was so "stuffed up by all the shit that went on here" he became "scared of ghosts" and now lives with his mother. Daniel tells me his own exasperated mother says of Alex, "Live with God! I've done all I can. Too bad." His father is humiliated and wants to hide. "But he can't. He can't go to Anzac Day marches because of the surname, and when people ask how his boys are, he says he's sorry my brother was ever born." After my visit, Daniel informs his parents he's spoken to a journalist, then forwards me the texts they sent him in response. From Maria: "You are sick stop your stupidity get a life you have no right to even mention anybody I am sick of your shit stop now." From George: "very worry what shit told reporter abt alx see you tomorrow you bring family shame and killing parents." The next day, after George O'Sachy arrives at his house, Daniel tells me by phone that he no longer wants his comments used. He sounds sullen and uncomfortable. In the background, I can hear his father urging: "Say, 'I withdraw! I withdraw!' " Then George takes the phone. "We've had enough of this rubbish [about Leanne Thompson]," he blusters. "Daniel wishes to withdraw all his comments ... and that's the end of story."

Soon afterwards Daniel sends me a text that begins, "You're allowed to talk to me ..." When I phone, he sounds normal again. "Dad made me ring you," he says. "He was going crazy. But he's gone now, so that's all right." So is it okay for me to use the comments? Daniel: "Yeah, if you want. 'Cause I'm not going to take any legal action. I said what I said. They're trying to protect Alex, that's all there is to it. Then, when he gets out [of jail], he'll cause problems and I'll probably be lumbered with his shit ... He'll just get locked up again, that's all that will happen. Or someone will die." Lifeline: 131 114 Find Good Weekend on facebook – facebook.com/GoodWeekendMagazine