A songwriter/antiques dealer in Illinois named Ronald Selle sued the Bee Gees, claiming a song he wrote in 1975 called "Let It End" was the basis for "How Deep Is Your Love." The case went to a jury in 1983. The Bee Gees claimed that they had never heard "Let It End," and there was no evidence that they did (that song was never released - Selle made a home recording that he had sent to music publishers). The case was based on the similarities between the songs, and an expert witness for Selle - a musicologist named Arrand Parsons - tried to convince the jury through technical analysis of the notes that the Bee Gees plagiarized the song. The jury bought it, and ruled that the Bee Gees did copy Selle's song. The judge, however, nullified the verdict. Selle later appealed, and was once again rebuffed.
The case underscored the problem of juries making judgments on music, and it led to a landmark ruling that "striking similarities" between songs was not enough to prove plagiarism (something George Harrison would have appreciated
). Henceforth, a songwriter had to prove that the infringing party actually heard the song before the case could move forward. This is one reason why music publishers and songwriters refuse to hear most unsolicited material.