Cathedral of the Downtown
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Following the shooting of Mr. Burns, Waylon Smithers, Jr. woke up hung over with a vague memory of having shot someone after the town meeting. Smithers then noticed his own gun had been recently fired, and came to the conclusion that he must have shot Burns. Guilt-ridden, Smithers went to the Cathredal of the Downtown, sat down in the confessional booth and confessed to having shot Burns. Instead of a priest, however, Chief Wiggum was sitting in the other side of the booth. After Smithers finished his confession, Wiggum opened the curtain, said "That's all I needed to hear!" and arrested him. Wiggum apparently made a regular practice of using the cathedral's confessional booth to catch suspects, as he also said, "Boy, this thing works great" as he arrested Smithers.
Smithers was later proven innocent, however. Sideshow Mel watched the news coverage of Smithers' arrest, realized that Smithers couldn't have shot Burns and went to the police with the information. The man Smithers shot turned out to be Jasper Beardly, who was unharmed because Smithers had hit him in his wooden leg.
 Behind the Laughter