Gossmann was born in 1941 and was studying theology at Nuremberg when the killings began. He was nineteen.
Between 1960 and 1965 he shot seven people in and around Nuremberg and Munich, in banks, shops and on the street. He chose the middle of the day and, in several cases, the moment when church bells were ringing, so that the sound of the shot would be lost. The German press called him the Mittagsmoerder, the midday murderer.
Some of the killings were robberies and some were not. He told the court he had wanted to be an agent of death and to know what it was to take a life, and the accounts he gave shifted.
He was arrested in 1965, convicted, and sentenced to life imprisonment.
The timing is the detail that made the case famous in West Germany, and it is also the practical core of it: a man who worked out that a city makes a noise at a fixed time every day and used it. Nothing accessible records his release position or whether he is alive.