Infamous 'American Beauty' murder link with the toxicologist who was defence witness for wife killer Gerard Baden-Clay
Forensic toxicologist Michael Robertson was convicted Australian murderer Gerard Baden-Clay's expert defence witness
Dr Robertson was the boss and lover of an American woman who poisoned her husband in 2000
Kristin Rossum murdered Greg De Villers and covered his body in rose petals
Rossum worked as a toxicologist for Dr Robertson in San Diego, California
She is now serving a life sentence without parole for drugging De Villers
She claimed her husband suicided by overdosing with the drug fentanyl
Dr Robertson gave evidence that Gerard Baden-Clay's wife Allison could have overdosed on the drug Zoloft
By Candace Sutton
Fourteen years before he appeared as Gerard Baden-Clay's defence witness, Australian toxicologist Michael Robertson was involved in a case which gripped the U.S. - the 'American Beauty' murder.
Dr Robertson appeared at the Brisbane Supreme Court this month as one of the final witnesses in Gerard Baden-Clay's trial for the murder of his wife Allison.
He gave evidence in Baden-Clay's defence as to the levels of sertraline - the chemical in the antidepressant Zoloft - present in Allison Baden-Clay's body, and whether they indicated suicide by overdose.
Dr Robertson presented his credentials of more than two decades working as a respected forensic toxicologist to the court.
Michael Robertson (pictured, leaving the Brisbane Supreme Court on July 2) was the boss and lover of fellow toxicologist Kristin Rossum who murdered husband Greg De Villers in 2000 and covered his body in rose petals. Rossum, who was sentenced to life for first degree murder, claimed her husband suicided by overdosing with the drug fentanyl. Dr Robertson gave evidence that Gerard Baden-Clay's wife Allison could have overdosed on the drug Zoloft
Fall from grace: Despite a privileged background and good education, Kristin Rossum (pictured in handcuffs arriving at court) developed a methamphetamine habit in her teens. After marrying Greg De Villers, she started an affair at the San Diego Medical Examiners office with her boss, Australian Dr Michael Robertson. When her husband threatened to expose her drug habit and affair, she killed him
Doomed: When Kristin Rossum met Greg De Villers in 1995 she had a speed habit, but he helped her get over it by the time they married (pictured) in June, 1999. A year later she had embarked on an affair with the man she worked for in the county toxicology laboratory in San Diego. On November 2, paramedics were called to the couple's apartment where they found De Villers comatose on the bed and covered in rose petal
American beauty murder: In the 1999 film, American Beauty, the character played by Kevin Spacey fantasises about the character Angela in a bath of rose petals. When the following year toxicologist Kristin Rossum poisoned her husband and sprinkled him with rose petals to suggest suicide, the case became known as the American Beauty murder
Under cross-examination by Crown Prosecutor Todd Fuller, QC, Dr Robertson agreed that the levels could have been as a result of decomposition and she might not have taken any of the drug before her death.
Unbeknown to the jury or most people in the court, in November 2002, Dr Robertson had a close connection with a different murder trial.
In 2000, he had become romantically involved with a woman who was charged with first degree murder in what was dubbed the 'American Beauty' case for its similarities to the 1999 Kevin Spacey film of the same name.
Dr Robertson was the lover of Kristin Margarethe Rossum, who worked for him at the
San Diego County Office of the Medical Examiner, where he was chief toxicologist.
Short-lived: Kristin Rossum and Greg De Villers were married for a year but the relationship soured when she began having an affair with Australian toxicologist Michael Robertson and resumed her drug habit. She told her murder trial De Villers overdosed because he was unhappy in their marriage. Robertson, who has always denied any involvement in the case, gave expert testimony for Gerard Baden-Clay this month, saying levels of the drug Zoloft in Allison Baden-Clays body could suggest an overdose's
Pretty and promising: In 2000, accomplished Californian chemistry graduate and pretty blonde from a privileged background, Kristin Rossum, had a glittering future. But when she embarked on an affair with an Australian toxicologist, resumed her drug habit and then murdered her husband. She claimed her husband had committed suicide but a jury didn't believe her
No parole: Promising young science graduate turned convicted husband murderer Kristin Rossum is currently incarcerated in the Central California Women's Prison (pictured) where she is serving a life sentence for the poisoning death of her husband, Greg De Villers, in what became known as the American Beauty murder
When Greg De Villers threatened his wife Kristin Rossum with exposure of her affair with the boss, Australian toxicologist Michael Robertson, and her resumption of her methamphetamine habit, the honours chemistry graduate drugged him with a lethal dose of the powerful pain killer fentanyl, which she stole from the laboratory where she worked with her lover
Rossum was sentenced to life for killing her husband Gregory De Villers by poisoning him and covering him in rose petals, after he had threatened to expose her methamphetamine habit and her affair with Robertson.
One month after the murder, Robertson flew back to Australia. Although he was named as an unindicted co-conspirator in Ms Rossum's murder trial, he was never charged, and has denied any involvement ever since.
Dr Robertson, who now runs a forensic consulting service in Brisbane, told the Herald Sun that the Rose Petal case did come to mind when he was acting as an expert witness in the Baden-Clay trial.
Dr Robertson himself has said friends used to joke that he was a walking advertisement for the negative consequences of an extramarital affair.
Rossum claimed de Villers committed suicide, but she is currently an inmate at the Central Californian Women's Prison.
Sentenced to life: Kristin Rossum, now aged 37 and incarcerated in the Central California Women's Facility, has Rossum has filed several petitions to overturn her conviction on first degree murder of her husband Greg De Villers, all of which have been denied. In 2006, De Villers¿ family sued Kristin and San Diego County in a wrongful-death suit, after learning that she was selling the rights to her story
But back in 2000, Rossum was a beautiful blonde scientist with a privileged background and a promising future.
A former ballerina and child model who had grown up in the wealthy college suburb of Claremont, California, Rossum developed a methamphetamine habit as a schoolgirl.
She met De Villers, a French American in 1995. He helped her get off drugs and they married in 1999.
Meanwhile, she had started work at the Office of Medical Examiner (OME) in San Diego and was appointed as a toxicologist when she graduated with her degree in chemistry.
Michael Robertson began work around the same time and was Rossum's supervisor. According to United States Court of Appeal evidence the pair began a sexual relationship in June 2000, and Rossum again began taking methamphetamines in October.
On November 2, 200, De Villers confronted Rossum about the drug use and her affair, demanded she resign from her job or he would expose the facts to the OME.
On the morning of November 6, she phoned her husband's workplace and called him in sick. She went to work, but returned to her apartment at lunchtime and was observed buying groceries.
She was back and forth from the apartment, met up with Robertson and spent the afternoon with him, then returned home.
It wasn't until 9.22pm she called 911 and reported De Villers was cold and not breathing.
Paramedics found Rossum on the phone and her husband lying on the couple's bed, covered in rose petals.
He was pronounced dead at 10.19pm and a San Diego medical examiner later concluded that he had been 'immobile and not breathing properly for approximately six to twelve hours prior to his death'.
A decision was made to perform toxicology tests on De Villers outside the San Diego OME, to avoid a potential conflict of interest, but before the specimens were sent away some of them were handled by Dr Robertson.
Gerard Baden-Clay was convicted on Tuesday of murdering his wife Allison and sentenced to life in prison
Nigel Baden-Clay (left) arrived at Wolston Correctional Centre to visit his son Gerard in prison in western Brisbane on Thursday
Tests showed that de Villers's organs contained extremely high concentrations of fentanyl, a painkiller up to 150 times more powerful than morphine, as well as a smaller amount of clonazepam, and a trace level of oxycodone, also known as 'hillbilly heroin'.
The OME conducted an audit on its impounded drugs and discovered that fifteen fentanyl dermal patches and ten milligrams of fentanyl were missing.
Their records showed Kristin Rossum had logged in the fentanyl standard and had worked on each of the three cases in which the missing fentanyl patches had been impounded.
The OME also determined that quantities of methamphetamine, clonazepam, and oxycontin (a time-released form of oxycodone) were missing.
Rossum told police her husband had committed suicide. Despite the suspicions of De Villers' family, San Diego police made no arrest.
But in December, the San Diego OME fired Rossum and Robertson, and he returned to Australia.
On June 25, 2001 San Diego police charged Kristin Rossum with murder. Her trial began in October 2002, with the defence counsel arguing De Villers had committed suicide by taking fentanyl because he was despondent over his marital problems.
Prosecutors in Rossum's trial alleged Dr Robertson helped his then-lover steal the fentanyl from the laboratory, which she administered to her husband to kill him.
Evidence included passionate emails exchanged between Dr Robertson and Rossum, as well as computer files and professional writings revealing Dr Robertson's specialist knowledge of fentanyl.
The jury found her guilty and in December 2002, the court sentenced her to life without parole.
Rossum has since filed several petitions to overturn her conviction, all of which have been denied.
In 2006, Greg de Villers' family sued Kristin and San Diego County in a wrongful-death suit, after learning that Kristin was selling the rights to her story.
A San Diego jury ordered Rossum pay $100 million in punitive damages, which was reduced to $10m.
After he returned to Australia, Dr Robertson has worked as a senior scientist and laboratory manager, as a toxicology consultant to industry and as an expert court witness.
According to his company, Independent Forensic Consulting , Dr Robertson is 'one of only a few independent, fully-trained and qualified clinical and forensic toxicologist's practicing in Australia'
He is 'an expert in drug and alcohol-related matters with over 20 years experience both nationally and internationally' and has 'been involved in some of the most complicated national and international cases and ...testifies regularly throughout Australia'.
'American Beauty' murder link with toxicologist who was Gerard Baden-Clay's defence witness
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