British actress Emma Thompson has been given the go-ahead to proceed with a movie about the lives of 19th century poet John Ruskin, his wife Effie Gray and her lover, painter John Everett Millias, after a judge threw out a New York playwright's copyright infringement claim last week (ends22Mar13).

Gregory Murphy alleged Thompson's screenplay for Effie infringed on his play The Countess, which was a hit on Broadway in 1999 and London's West End in 2005, but the film's producers insisted the Love Actually star had no access to Murphy's play and did not copy it, and now a judge has thrown out the playwright's claims, according to Britain's The Guardian newspaper.

Judge Thomas P Griesa has declared, "The shooting script of the film Effie is not substantially similar to either the stage or screen version of The Countess. The shooting script of Effie does not infringe Murphy's copyrights in The Countess."

Murphy is upset about the decision and tells Britain's Sunday Telegraph, "It appears to be virtually impossible for a writer to win in a declaratory judgment brought against him. The bar for proving 'substantial similarity' with a script that draws on historical fact is extremely high.

"This is especially true, when, as was the case here, the bar moves during the case. Emma Thompson was allowed by the court to submit a second script from which she removed some of the most troubling material. Allowing her to substitute scripts in the middle of a case is, I believe, unprecedented."

Last year (12), a New York court threw out a claim by American writer Eve Pomerance, who claimed the screenplay for Effie derived from her work The Secret Trials of Effie Gray.