Johnny Depp has lost his defamation case against a British tabloid newspaper that accused the Hollywood star of assaulting his ex-wife Amber Heard.

London's High Court has refused to award the Pirates of the Caribbean star compensation for damage to his reputation over the 2018 article by The Sun that accused him of being a "wife beater" while married to Heard.

The verdict follows three weeks of courtroom drama that unearthed extraordinary revelations about the marriage of Depp, 57, and Heard, 34, who was The Sun's star witness.

In his ruling, High Court judge Andrew Nicol found the newspaper's claims were "substantially true".

"The claimant has not succeeded in his action for libel," Judge Nichol said.

"Although he has proved the necessary elements of his cause of action in libel, the defendants have shown that what they published in the meaning which I have held the words to bear was substantially true."

The judge ruled Depp's feelings towards his wife during their turbulent three-year relationship were summed up in a text where the actor revealed he had "no mercy" for her.

He also concluded Depp beat Ms Heard 12 out of 14 times - starting in 2013 when he slapped the actress when she made a comment about his tattoo.

He dismissed two allegations made by Ms Heard in 2014 and 2015 but said he couldn't conclude she had been "untruthful" about it.

Depp had sued The Sun's publisher, News Group Newspapers, and its executive editor, Dan Wootton, over an article that carried the headline: "Gone Potty: How can JK Rowling be 'genuinely happy' casting wife beater Johnny Depp in the new Fantastic Beasts film?".

Depp strenuously denied he had been abusive towards Heard during their two-year marriage.

The three-week trial unearthed details of the couple's tumultuous relationship, including wild arguments and Depp's battles with drugs and alcohol, and that he had smeared "I love you" on a mirror in blood while the couple were in Australia.

Heard told the court Depp had sent her texts calling her "a fat ugly w***e" and also sent messages to British actor Paul Bettany, in which he plotted to drown and burn her as a witch and "f**k her burnt corpse afterwards to make sure she's dead".

Lawyers for Depp had argued the messages should not be taken seriously, "however dark and extravagant the language".

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