After his mistress, Juliana Blasius, was threatened with being charged as an accomplice, Schinderhannes rolled over and testified against his fellow gangsters. Nineteen of his associates were sentenced to death. Despite his cooperation, Schinderhannes was sentenced to death as well. On September 21, 1803, he was guillotined before the gates of Mainz. More than 40,000 spectators witnessed his execution. He remains Germany's most famous outlaw. His legend still attracts a great deal of tourism to the region wherein his gang operated.

He did 130 crimes, mostly thefts, extortions and robberies which could be proven to date.