J. K. Rowling heard her work described as “gibberish” by a US judge yesterday at the end of a three-day trial into an unauthorised encyclopaedia of her Harry Potter novels.

Rowling has asked the federal court in New York to block publication of The Harry Potter Lexicon, a guide to the characters, places and spells in her novels, written by Steven Vander Ark, 50, a former school librarian.

District Judge Robert Patterson Jr said that he had read the first half of the first Harry Potter novel to his grandchildren, but found the “magical world hard to follow, filled with strange names and words that would be gibberish in any other context.

“I found it extremely complex,” he said, suggesting that a reference guide might be useful.

Rowling said she was “vehemently anti-censorship; and generally supportive of the right of other authors to write books about her novels”. But she said Vander Ark had “plundered” her prose and merely reprinted it in an A-to-Z format.

A decision in the case is not expected soon. It will be weeks before lawyers finish filing documents, and possibly longer before a verdict is given. Judge Patterson is deciding the case, rather than a jury.

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