It’s been widely reported in the news and on this blog—a jury in a Federal copyright infringement case has reached a verdict favoring legendary rock band Led Zeppelin, finding that it did not plagiarize the iconic guitar riff from the band’s hit song “Stairway to Heaven.” However, almost nobody is talking about the law behind that verdict.
In the law of copyright, just how similar is too similar when it comes to music? We all know that in the world of popular music, musical styles come and go. There is no question that when a certain “sound” becomes popular, that sound will influence and be echoed by other artists. However, by what standard does the law judge if a musical work is too similar to a prior work?
Among the things that must be proven in any case of infringement of a musical work protected by copyright is that the alleged infringer copied protected elements of the original work. Swirsky v. Carey (9th Cir. 2004) 376 F.3d 841, 844. That may be done by showing that the new work is “substantially similar” to the original work. Two tests are employed by the courts in the 9th Circuit, an “objective extrinsic test” and a “subjective intrinsic test.” Id.
The objective extrinsic test turns on “whether two works share a similarity of ideas and expression as measured by external, objective criteria.” Id. This requires an “analytical dissection,” basically breaking the work down into particular components and comparing them for similarities. Any infringement case involving musical works will involve musicology experts opining on matters such as rhythm, tempo, pitch, chord changes, lyrics, and other stylistic and compositional elements. The courts have observed that there is no “uniform set of factors to be used” in judging the compositional similarity of two works. Swirsky v. Carey, supra, 376 F.3d 841 at 849.
The subjective intrinsic test turns on “whether the ordinary, reasonable person would find the total concept and feel of the works to be substantially similar.” Three Boys Music Corp. v. Bolton (9th Cir. 2000) 212 F.3d 477, 485, quoting Pasillas v. McDonald’s Corp. (9th Cir.1991) 927 F.2d 440, 442.
Another relevant consideration in the Ninth Circuit’s infringement jurisprudence is what is known as the “inverse-ratio rule.” Under that rule, the greater the showing made as to the actual access to the original work by the alleged infringer, the less rigorous the showing of substantial similarity must be. Three Boys Music Corp. v. Bolton, supra, 212 F.3d at 486. In other words, if the evidence were to show that a songwriter had seen the original work performed just before writing his or her hit song that supposedly infringed that original work, then less evidence is required to prove the substantial similarity between the two works. In the Stairway to Heaven case, the plaintiff offered evidence that Led Zeppelin and the plaintiff’s band Spirit had toured together and Spirit had performed the song that included the opening guitar section that Led Zeppelin had allegedly copied. Access aside, the jury concluded that the works were not sufficiently similar.
Accordingly, infringement of a musical work involves a complicated analysis under the law. That analysis can turn on circumstantial evidence as to how the songs came about, as well pure musical theory. So all that glitters is not necessarily gold in the law of music infringement.