The episode highlights the inquisitorial role of judges in French criminal cases.
Gaston Meurant (Patrick Troughton) a picture framer is accused of murdering his aunt and smothering a small child who stayed with her as a boarder.
Gaston had money troubles and his aunt kept money in a large jar.
Maigret believes it is a solid case, he was sent some items of clothing from Gaston's wife, one of them had blood stains.
By the time of the court hearing Maigret has doubts. He learns that Gaston's wife has been having an affair with another man.
Maybe she framed her own husband. He needs to track down her lover as one Gaston is free, he might go after him.
There was some nice touches as Maigret is frustrated as he tries to track down a file with a picture of the new suspect.
The laughter of the courtroom spectators as Maigret tells the judges why he changed his mind regarding the accused.
There is a nice understated performance from Troughton.