Former nurse Niels Högel pleaded guilty to killing 100 patients between 2000 and 2005, injecting his targets with a mixture of drugs, sending them into cardiac arrest.
Högel carried out the mindless murders at two hospitals in the cities of Oldenburg and Delmenhorst. Investigators have suggested he killed the patients out of “boredom” or to demonstrate his medical expertise.
A minute of silence was observed prior to the trial, which was held in a nearby hall to accommodate all of the plaintiffs and legal support staff.
The 41-year-old was jailed for murdering two patients in 2015, but investigators later discovered the extent of his crimes were likely to be much greater than previously thought.
After confessing to murdering over 100 German patients, Högel is now one of the most prolific serial killers in Germany’s modern history, and investigators are continuing to look for answers.
"We will do our utmost to learn the truth. It is like a house with dark rooms — we want to bring light into the darkness,” Sebastian Bührmann, the presiding judge, said on Tuesday.