The Duke of Sussex last year joined a group of high-profile figures, including singer Elton John, in legal action against the publisher of the Daily Mail, the Mail on Sunday and the Mail Online.

The lawsuit accuses Associated Newspapers Limited (ANL) of engaging in various means of criminal activity to obtain information on high-profile figures over the years.

Elizabeth Hurley, Sadie Frost, David Furnish and Doreen Lawrence make up the rest of the plaintiffs behind the legal action.

They claim they were “victims of abhorrent criminal activity and gross breaches of privacy,” according to a statement from their representatives at the time.

The group has accused ANL of hiring private investigators to carry out unlawful acts such as planting listening devices in homes and cars and recording private calls. It also claims the publisher would pay corrupt police officials to obtain inside information, engaged in impersonation and deception to obtain medical records, and would hack into bank accounts and financial transactions by “illicit means and manipulation.”

Monday is the start of a four-day preliminary hearing at London’s Royal Courts of Justice, during which ANL is expected to try and have the case thrown out.

The publisher has rejected the allegations as “preposterous smears” and labeled the lawsuit as a “preplanned and orchestrated attempt to drag the Mail titles into the phone-hacking scandal,” according to PA Media.

An ANL spokesperson added that the claims were “unsubstantiated and highly defamatory claims, based on no credible evidence,” PA reports.