Answer / Solution to the Inspector Beethoven III Puzzle

This is the solution to the Inspector Beethoven III puzzle posted on 31st January. Those who haven't tried it yet, Go for it at Inspector Beethoven III Riddle

Strauss is the one who killed Handel.
You need to take turns assuming someone is the killer; that means everyone's second sentence is a lie. If Joplin was the killer, Grieg's lie mixed with Strauss' counteracts the other. If Grieg was the killer, Gershwin would need to be a killer too. If Gershwin was the killer, Grieg and Strauss counter each other again, but with Strauss, everything would fit.

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