Susan Nelles

The Toronto hospital baby deaths were multiple alleged poisonings of babies at Toronto's Hospital for Sick Children that occurred between June 1980 and April 1981, when charges of murder were laid against a nurse at the hospital. The story was a major news event throughout the year, and ended with the nurse being exonerated. Although suspicion was cast on other people, no further charges were ever laid.

Later analysis suggests that the tests and methodologies that pointed to poisoning were flawed, and may have been generating false positives. Specifically, chemicals used in the manufacture of everyday medical items may have contributed to the test indicating high levels of the alleged poison. It was also demonstrated that a "wave" of similar alleged poisonings were occurring at that time.

During an investigation of baby deaths in the cardiac unit of the Hospital for Sick Children, abnormally high levels of the heart medication digoxin were found in as many as 43 of the infants. The levels were measured using a newly introduced testing method known as HPLC, and the levels were high enough to suggest that it was the cause of death.

A police investigation followed during which time it was found that a nurse that the hospital had been working shifts during the times that 23 of the deaths occurred. Susan Marguerite Nelles (born in Belleville, Ontario), was arrested and charged in March 1981 with murdering four babies. The deaths then stopped.

During the case that followed, it was discovered that Nelles had not actually been on duty during the noted times, having swapped shifts with other nurses who had access to the same medication. Although the deaths ended after Nelles' arrest, the hospital had introduced restrictions for access to digoxin and had implemented a policy that kept infants in intensive care longer. Total deaths between the two units remained identical.

Nelles asked for legal counsel when she was arrested. Her request was interpreted by the investigating police officers to be an indication of her guilt, but the court later ruled that such requests should not be interpreted as evidence of guilt. The court also ruled that the Crown lacked evidence to convict Nelles. The government eventually paid for Nelles' legal costs after she sued the province's Attorney-General, Roy McMurtry for malicious prosecution.

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Wikipedia