Music copyright infringement cases often depend on expert witness testimony. The expert witness (typically a musicologist) testifies about similarities between the plaintiff's and defendant's works and opines that the similarities do or do not establish copying. The use of expert testimony in music infringement cases rests on the belief that a person with musical training can determine whether similarities between two musical works are merely coincidence or proof of copying. The truth of this proposition may seem obvious, but closer reflection suggests that the foundation for expert opinions about copying is questionable. The weaknesses become apparent when one compares music infringement cases with other cases based primarily on coincidence. This presentation will offer an example of such a comparison by invoking the tort doctrine of res ipsa loquitur and the use of expert witnesses in such cases.