"The clothes on the hanger do nothing. The clothes on the woman do everything," Breyer said during an argument about whether the design of cheerleading uniforms can be protected under copyright law.
Justice Elena Kagan chimed in to say Breyer's words were "so romantic."
The case pits Varsity Brands, the leading manufacturer of cheerleading uniforms, against Star Athletica.
But the justices and the companies' lawyers invoked Dutch painter Piet Mondrian, French artist Marcel Duchamp, clothing designer Stella McCartney, actor Kate Winslet and gorilla suits as they tried to figure out whether the design of cheerleading uniforms can be protected under copyright law.
There was a lot of talk about stripes and chevrons, and how they make cheerleaders look slimmer, taller and curvier.
Would the result be different if stripes "were stitched instead of applied?" Chief Justice John Roberts asked.
Varsity sued Star for copyright infringement based on Star's 2010 catalog that used designs that Varsity claimed as its own. A federal appeals court agreed with Varsity.
In its Supreme Court appeal, Star argued that the designs on cheerleading uniforms can't be separated from the uniforms themselves, and that if Varsity has its way, it would have a monopoly on the uniforms.
Fashion designers are siding with Varsity while makers of gorilla suits and other costumes are backing Star.
Justice Sonia Sotomayor worried that if Varsity prevails, brand-name clothing manufacturers would have more power. It would be "killing knockoffs with copyright," Sotomayor said.
Breyer used a reference to the art world to try and make sense of Star's argument. Duchamp, who used found objects in his works, could hang a shovel on a wall and call it art, Breyer said.
But the artist couldn't "sue people who make shovels," Breyer said.
A decision in 15-866, Star Athletica v. Varsity Brands, is expected by spring.
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