Der Richter und sein Henker is a novel by the Swiss writer Friedrich Durrenmatt written in the year 1952. The literal translation of the title is: The Judge and His Henchman.
The main character is Commissioner Bärlach, who is about to die and must solve a murder from Bern with his assistant Tschanz. He encounters his old friend/enemy Gastmann, whom Tschanz suspects is the murderer. Bärlach discovers that Tschanz was the murderer, and Tschanz admits to using Gastmann to cover it up.
Gastmann and Barlach go back twenty years. Gastmann remembered to Bärlach: "I wanted to prove that it was possible to commit a crime that couldn't be solved." Gastmann was right. The central question of this book is whether or not it is right to frame a person for a crime they didn't commit when they committed another crime that was never solved. Bärlach affirms the question when he says to Gastmann: "I couldn't prove that it was you who committed the first crime, but I am transfering this crime to you" - therefore, Gastmann was defeated.
One can understand the novel also as question: "When humans determine themselves, the fate of others they become the judges and when they become the instrument of others they become the henchmen. Tschanz says to Bärlach at the end of the story, "Then you were the judge and I the henchman". He then kills himself.
Source: Der Richter und Sein Henker (Translation)