Waltraud Wagner was born in 1959 and worked as a nurse's aide on Pavilion Five at the Lainz General Hospital in Vienna, a large geriatric ward.
Between 1983 and 1989 she and three colleagues, Maria Gruber, Irene Leidolf and Stefanija Mayer, killed elderly patients on the ward. They used overdoses of morphine and insulin, and a method Wagner devised of holding a patient's nose and tongue and pouring water into the mouth so that the lungs filled, which in an elderly patient produces a death that looks entirely natural. It became known in the case as the water treatment. Austrian reporting called the four women the Lainz Angels of Death, after the hospital.
It began as what Wagner described as mercy for a patient who had asked to die, and became something else. The women killed patients who were difficult, who soiled themselves, who complained, or who snored.
They were caught in 1989 when a doctor overheard them laughing about a patient's death in a tavern and reported it.
Wagner was convicted in March 1991 of fifteen murders, seventeen attempted murders and two counts of aggravated assault, and sentenced to life. The three others received terms of between fifteen years and life. The final total is not known and was estimated at trial as considerably higher than forty-two. She was released in 2008 and lives under another name, which caused a substantial public row in Austria.
The Lainz case produced reform of Austrian hospital supervision and remains the largest medical killing case in the country's history.