Judge Judith Barzilay huddled late last year with a telepathic professor and a cast of mutants to ponder an age-old question: What does it mean to be human?

In her chambers at the U.S. Court of International Trade, in New York, the judge examined Prof. X and the rest of his band of X-Men, all of them little plastic figures at the heart of a six-year tariff battle between their owner, Marvel Enterprises Inc., and the U.S. Customs Service.

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