As British pop star Ed Sheeran juggles preparations for a major tour and album release, he also faces a critical copyright lawsuit in Manhattan's federal court. The case questions whether Sheeran's 2014 hit "Thinking Out Loud" plagiarized Marvin Gaye's 1973 classic "Let's Get It On." The civil suit, filed by the heirs of Gaye's co-writer Ed Townsend, alleges notable similarities between the two songs.

This lawsuit is among several recent high-profile music copyright cases causing unease in the industry and making songwriters increasingly wary of their creative processes and potential litigation risks. Sheeran, 32, has spent days in court testifying and playing demos with his guitar to demonstrate that the 1-3-4-5 chord progression, the primary point of contention, is a fundamental aspect of pop music that cannot be copyrighted.

Sheeran's legal team argues that Gaye and Townsend were not the first to use the chord progression, citing examples from Van Morrison songs predating "Let's Get It On." Forensic musicologist Joe Bennett echoes this sentiment, stating, "The world I want to live in is one where nobody sues anyone for a one- or two-bar melodic or harmonic similarity because those similarities can so easily occur through coincidence."

The case focuses on the actual compositions of the songs, not the recorded versions, which could potentially work in Sheeran's favor. However, once a music copyright lawsuit reaches a jury trial, the outcome is uncertain. Convincing a jury requires substantial funding and resources, and defendants are subject to the unpredictable opinions of jurors who likely lack musicology expertise.

The trial has seen both parties employing expert witnesses to present technical details to the jury, but their findings differ significantly. Bennett acknowledges the risks, saying, "If you play music to a jury, it could go either way."

A spate of landmark music copyright cases in recent years has raised questions about the future of the industry. The 2016 ruling in favor of Gaye's family in their lawsuit against Robin Thicke and Pharrell Williams over the song "Blurred Lines" left many surprised. The decision reinforced the belief that foundational musical elements should be considered part of the public domain.

As the Sheeran case unfolds, songwriters are growing increasingly concerned about the potential chilling effect on their work. Unintended infringement is not a strong defense, as George Harrison discovered in 1976 when he was found liable for "subconsciously" plagiarizing "He's So Fine" by the Chiffons in his solo hit "My Sweet Lord." The Sheeran trial has sparked fears among the next generation of songwriters, who worry that the creative and emotional aspects of songwriting may be jeopardized in the pursuit of complete originality and uniqueness.