Gaston Meurant has to answer to a Parisian jury court for the robbery and murder of his aunt. He has been convicted on what appears to be a complete chain of evidence. But shortly before the sentence is pronounced, Maigret comes across exculpatory material with which he manages to free the accused. The experienced detective hopes that Meurant will now provide him with clues about the real murderer. So he also has Meurant's wife Ginette and her lover under surveillance... Based on the 55th Maigret novel Maigret aux assises (1959), published in German under the title Maigret vor dem Schwurgericht. Originally the novel was published in 21 sequels in Le Figaro between 15.04.1960 and 19.05.1960.