Isabella Mueller (crime writer)
It was a cool autumn morning in 1977 when two concerned ladies walked into the Tübingen Institute unannounced. Holding a jar of blackberry compote in their hands, they asked for it to be tested for the presence of poison. What initially appeared to be a trivial enquiry was soon to develop into one of Germany’s most insidious cases of poisoning, in which the perpetrator had acted with a cold-bloodedness and cruelty that shocked even seasoned forensic scientists. The story began with the tragic plight of a seriously ill woman named Ingeborg R., who was being treated at Ulm University Hospital for acute liver failure and ascites. The patient, whose condition had already been stabilised on several occasions through inpatient treatment, repeatedly suffered the same symptoms as soon as she returned home. The patient’s husband, a respected chemistry teacher named Siegfried R. at the Schubart Gymnasium in Ulm, seemed particularly keen for his wife to consume the blackberry compote he had brought to her bedside as quickly as possible. This conspicuous urgency gave rise to the first suspicions. During a confidential conversation, one of the two women – the patient’s sister-in-law – described the suspicious circumstances. Her suspicions had been aroused when the husband repeatedly insisted that his wife should eat the compote, often accompanied by urgent telephone calls. A small taste had immediately triggered nausea in the patient, similar to her initial episode. Fearing she might trigger further symptoms, she contacted her sister-in-law and decided to have the compote analysed. Analysing the blackberry compote presented the institute with a challenge. After an initial test feeding on white mice, all of which died within 12 hours, it was clear that it must contain a highly toxic substance. But what exactly was it? Following extensive tests, it emerged that the poison was nitrosodimethylamine, a highly toxic compound that is hepatotoxic and carcinogenic. Quantitative analysis of the blackberry compote revealed that it contained approximately 500 mg of this dangerous substance. The findings were immediately forwarded to the criminal investigation department, which arrested the chemistry teacher whilst he was still on duty at the school. The accused admitted to having added the poison but denied any intention to kill. His defence claimed that his wife’s life-threatening illness must have had other causes, as the compote had not been consumed. Nevertheless, criminal investigations proved that the teacher had begun ordering nitrosodimethylamine as early as 1975, coinciding with the publication of an article on chemical carcinogens in the journal Chemie unserer Zeit, which he had read. It emerged that Siegfried R. had purchased 25 ml of nitrosodimethylamine from Merck on three separate occasions, using the school’s budget. He intended to kill his wife slowly by adding small doses of the highly toxic substance to her food and drink over a period of years. But why did Siegfried R. want to kill his wife in such a painful way? Siegfried R. enjoyed an impeccable reputation as a senior teacher; to the outside world, as a father of two, he and Ingeborg led a picture-perfect marriage. But this was all just a façade, for Ingeborg had cheated on Siegfried with their family doctor. When the doctor died in an accident in 1969, the couple decided to give their marriage another chance. But Siegfried was deeply hurt and had nothing but revenge on his mind. The situation came to a head when he began an affair with a female colleague 23 years his junior. As divorce was out of the question for financial reasons, he made the crucial mistake of serving the poisoned blackberry compote, because Ingeborg was not dying quickly enough. Had he not made this mistake, it would have been the perfect murder. The court recognised that Ingeborg’s illnesses had been caused by repeated administrations of poison. The first dose of poison was presumably administered at the end of 1975 and led to severe liver disease. These acts were classified as attempted murder, as Siegfried knew full well that the poison is metabolised quickly and is therefore difficult to detect. The verdict was attempted murder, and the chemistry teacher was sentenced to life imprisonment. This verdict is still regarded as a precedent today, as no one had ever before been sentenced to life imprisonment for attempted murder. Shortly after the trial ended, Ingeborg died as a result of liver failure. Siegfried R., better known as the ‘Blackberry Murderer’ – as he was dubbed by the media – died of stomach cancer in October 1984 at the Hohen Asperg prison hospital after serving six years of his sentence. Until his death, he had set up a pilot scheme within the prison system in which he taught fellow inmates and helped them to obtain school-leaving qualifications. Despite these tragic outcomes, the case served as a reminder to the public of just how far human malice can go and what an invaluable contribution forensic science can make to justice.
