The Toronto hospital baby deaths occurred in the Cardiac Ward of the Hospital for Sick Children between July 1980 and March 1981. The deaths started after a cardiology ward had been divided into two new adjacent wards. The deaths ended after the police had been called in, and the digitalis-type medication that had possibly been used for the alleged killings (digoxin) had begun to be kept under lock and key. Three nurses were at the centre of the investigation and an apparent attempt to poison nurses' food. One of the nurses, Susan Nelles, was charged with four murders, but the prosecution was dismissed a year later on the grounds that she could not have been responsible for a death excluded in the indictment, which the judge deemed a murder.