Emma Thompson has won a landmark US ruling allowing her to move forward with her forthcoming period drama Effie, about the famous love triangle between art critic John Ruskin, his teenage wife Effie Gray and pre-Raphaelite painter John Everett Millais.
Thompson had been accused of plagiarism by the American writer Eve Pomerance, author of two unfilmed screenplays about the Victorian scandal titled The King of the Golden River and The Secret Trials of Effie Gray. The timing of the ruling in the Oscar-winning actor's favour could not be more vital, since Effie is due for release in May, with Thompson herself joining Dakota Fanning, Orlando Bloom and Robbie Coltrane in the cast.
New York district judge J Paul Oetken noted the difficulty of determining copyright infringement in the historical fiction realm where US laws did not protect repetition of known historical facts, only the purloining of imaginative ideas relating to them. In a 61-page ruling, he granted Thompson's production company Effie Film a declaration of non-infringement, the British writer having sued following threats of litigation from Pomerance.
Greg Wise plays Ruskin in Effie, with Fanning as his virginal teenage wife and Tom Sturridge as Millais. Historically, Gray sat for Millais in 1851 after being championed by Ruskin, and the painter and his subject are said to have fallen in love soon afterwards. It was swiftly discovered that Ruskin had never consummated the marriage, and the union was later annulled. Millais and Gray went on to marry and she bore him eight children. Nevertheless, the annulment caused a great scandal.
The episode gave rise to Ruskin's famous comment on his reasons for failing to consummate the marriage to his young bride. "It may be thought strange that I could abstain from a woman who to most people was so attractive," he told his lawyer during the annulment proceedings. "But though her face was beautiful, her person was not formed to excite passion. On the contrary, there were certain circumstances in her person which completely checked it."
Thompson's production company is also engaged in litigation against a separate copyright threat from US playwright Gregory Murphy, who contends that Effie is based on his play The Countess about the same Ruskin-Millais scandal. Murphy's creation opened in 1999, playing 634 times in New York and was revived for the London stage in 2005. Thompson denies copying the play, and says she never had access to it. The case has not yet come before a court.
• This article was amended on 19 December. The original stated that Orlando Bloom plays Ruskin. We also added details of playwright Gregory Murphy's copyright claim against Emma Thompson's production company. This has been corrected.
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