Suspicions were raised after it became obvious to friends and neighbours that Bluey Fletcher was suffering from the same fatal illness that had killed Yvonnes first husband. A police investigation led to the exhumation and testing of Desmond Butlers remains, which showed clear evidence of thallium, and this led to Yvonne being convicted of Butlers murder. She was sentenced to death but the sentence was commuted to life imprisonment after the NSW Government abolished the death penalty; she was eventually released in 1964. At the time of the trial it was reported that this was the first known case in Australia of a person being convicted of murder by administering thallium. The Fletcher case is also notable for the fact that one of the arresting officers was Sydney detective Fred Krahe, who later became notorious for his suspected close involvement with elements of Sydneys organised crime scene and his alleged involvement in the disappearance of social activist Juanita Nielsen. A month later, in October 1952, Bathurst grandmother Ruby Norton was tried for the murder of her daughters fiancé, Allen Williams, who died of thallium poisoning at Cowra Hospital in July 1952. Despite allegations that Norton hated all the men in her family and that she did not want Williams as a son-in-law, Norton was acquitted. In 1953 Sydney woman Veronica Monty, 45, was tried for the attempted murder of her son-in-law, noted Balmain and Australian rugby league player Bob Lulham, who was treated for thallium poisoning in 1952.
First known was to use Prussian blue, which is a solid ion exchange material, which absorbs thallium. Up to 20 g per day of Prussian blue is fed by mouth to the person, and it passes through their digestive system and comes out in the stool. Hemodialysis and hemoperfusion are also used to remove thallium from the blood stream. At later stage of the treatment additional potassium is used to mobilize thallium from the tissue. Notable cases
There are numerous recorded cases of fatal thallium poisoning. Because of its use for murder, thallium has gained the nicknames "The Poisoners Poison" and "Inheritance Powder" (alongside arsenic). Australias "Thallium Craze"
In Australia, in the early 1950s, there was a notable spate of cases of murder or attempted murder by thallium poisoning. At this time, due to the chronic rat infestation problems in overcrowded inner-city neighbourhoods (notably in Sydney), and thalliums effectiveness as a rat poison, it was still readily available over the counter in New South Wales, where thallium sulphate was marketed as a commercial rat bait, under the brand Thall-rat . In September 1952 Yvonne Gladys Fletcher, a housewife and mother of two from the inner Sydney suburb of Newtown, was charged and tried for the murders of both her first husband, Desmond Butler (who died in 1948), and her abusive second husband, Bertrand "Bluey" Fletcher, a rat-bait layer, from whom she had obtained the thallium poison that she used to kill him earlier that year.