Weidenbroeker was born in 1964 and lived at Broichweiden in North Rhine-Westphalia, where he was serving an apprenticeship as a chemist.
Between 1982 and 1986 five girls and young women aged sixteen to nineteen died in the area: Marta Habermann, nineteen; Karen Fink, sixteen; Doris Schroeder, eighteen; Elke Braun, seventeen; and Beate Goertz, eighteen. They were stabbed or drowned, and were sexually assaulted, in several cases with an object.
He was arrested and tried, and sentenced to life imprisonment on April 10, 1987.
The range of one to five is the important part of this entry. The conviction covers one killing; the remaining four were attributed to him and were not established at trial. The German record accessible here does not set out which, or on what evidence the attribution rested.
The sourcing is an encyclopaedia entry and brief contemporary reporting. The entry is written on the single conviction, with the four noted as attributions.