Why did the musician get arrested?

This punchline is a masterclass in musical wordplay, hitting you with a delightful one-two punch of puns. The phrase "major key scandal" cleverly swaps a fundamental music theory concept for the idea of a large, newsworthy controversy. The joke then doubles down with the musician being "in treble," which is a perfect sound-alike for being "in trouble," using the term for high-pitched musical notes.

The humor works by creating an absurd scenario where a musician's legal problems are described in purely musical terms. While plenty of artists have had their share of real-world scandals, this joke imagines a world where their crimes are related to harmony and pitch. A major key is one of the most common and foundational scales in Western music, often sounding bright and happy, making the idea of a "scandal" involving one even more ridiculous. It’s a sharp and funny gag for anyone who's ever seen a treble clef on a sheet of music.