The Duke of Sussex and Sir Elton John are among several other famous faces who are suing Associated Newspapers over allegations of "abhorrent criminal activity".
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Legal filings made on Thursday 6 October show that Baroness Doreen Lawrence of Clarendon OBE, Prince Harry, Elton John and David Furnish, Elizabeth Hurley and Sadie Frost have accused the newspaper group, which owns Daily Mail and Mail on Sunday, of "gross breaches of privacy".
Harry, Elton and David are among those filing the lawsuit
Unlawful acts alleged to have taken place include "the hiring of private investigators to secretly place listening devices inside people’s cars and homes, the commissioning of individuals to surreptitiously listen into and record people’s live, private telephone calls whilst they were taking place, the payment of police officials, with corrupt links to private investigators, for inside, sensitive information, the impersonation of individuals to obtain medical information from private hospitals, clinics, and treatment centres by deception, the accessing of bank accounts, credit histories and financial transactions through illicit means and manipulation".
The filling goes on to claim that "the alleged crimes listed above represent the tip of the iceberg - and that many other innocent people remain unknowing victims of similar terrible and reprehensible covert acts".
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The six have now shared that they plan to "hold the journalists responsible fully accountable, many of whom still hold senior positions of authority and power today".
A spokesman for Associated Newspapers said in response: "We utterly and unambiguously refute these preposterous smears which appear to be nothing more than a pre-planned and orchestrated attempt to drag the Mail titles into the phone hacking scandal concerning articles up to 30-years-old. These unsubstantiated and highly defamatory claims, based on no credible evidence, appear to be simply a fishing expedition by claimants and their lawyers, some of whom have already pursued cases elsewhere."
Elton is close friends with Harry and Meghan
Harry and his wife Meghan Markle previously sued Associated Newspaper Limited and in July secured a victory when a High Court judge has ruled that The Mail on Sunday's comments over the Duke's legal claim against the Home Office were indeed "defamatory".
In February, the paper ran a story under the headline, "Exclusive: How Prince Harry tried to keep his legal fight with the government over police bodyguards a secret… then – just minutes after the story broke – his PR machine tried to put a positive spin on the dispute."
In the ruling, Mr Justice Nicklin found that parts of the article in the claim were defamatory. He said the article did not suggest that Harry "was seeking to keep his 'legal battle' with the Government secret," though it was suggested by the headline if read alone.
The judgment only relates to the "objective meaning" of the article, Mr Justice Nicklin said, adding it is the first stage in the libel claim. This means the case can now go forward to a full trial.
Meghan thanked her husband Harry and mother for their support
In 2021 Meghan also won her High Court privacy claim against the Mail on Sunday over the publication of a "personal and private" handwritten letter to her estranged father, Thomas Markle.
In a statement, Meghan thanked husband Harry and her mother Doria Ragland for their support, and said she is "grateful to the courts for holding Associated Newspapers and The Mail on Sunday to account for their illegal and dehumanizing practices".
The Duchess, 39, sued for breach of copyright, infringement of her privacy, and breaches of the Data Protection Act over articles which showed parts of a letter she had written to her father, 76-year-old Thomas Markle, in August 2018.
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Meghan herself is also being sued by her half-sister Samantha Markle over her now-infamous interview with Oprah Winfrey in March 2021, as well as the material published in the Finding Freedom biography.
But Meghan's legal team have hit back, and have argued that Meghan's statements about her relationship with Samantha are "non-actionable opinion that are also substantially true".
They have requested a judge stop the process of collecting and releasing evidence until a ruling on whether the lawsuit should be entirely thrown out.