Meghan Markle won a bitter legal battle with the Mail on Sunday newspaper over a letter to her father

• Meghan Markle won a privacy claim against the Mail on Sunday, a judge ruled Thursday.
• The British newspaper published parts of a letter the duchess wrote to her father.
• The judge also said that the Mail breached copyright rules by publishing the letter.

Meghan Markle has criticized the British Mail on Sunday newspaper for its "illegal and dehumanizing practices" after winning a legal battle with the publication.

The Duchess of Sussex sued the publication, claiming that it misued her private information, infringed her copyright, and misused her personal data by publishing excerpts of a letter she wrote to her father.

The letter was provided by Thomas Markle to The Mail on Sunday in February 2019. The newspaper published excerpts from the letter under the headline: "Revealed: the letter showing true tragedy of Meghan's rift with a father she says has 'broken her heart into a million pieces.'"

On Thursday, a judge at the High Court in London sided with Markle.

Mr Justice Warby issued a "summary judgement" that the Mail misused her private information, which means that he decided the issue without a full trial.

"The claimant had a reasonable expectation that the contents of the Letter would remain private. The Mail Articles interfered with that reasonable expectation," Warby said in the official ruling.

He also ruled that the Mail's parent company Associated Newspapers had breached copyright by publishing the letter, a second victory for Markle.

However, he said that part of the case did require a full trial to determine whether the Mail's lawyers were correct to claim that she was not the only author of the document.

They argued that the outcome of the case - in which Markle is seeking damages - may depend on whether an official working for the royal family helped her draft the document.

Markle said in a statement obtained by Insider that she is "grateful to the courts for holding Associated Newspapers and The Mail on Sunday to account for their illegal and dehumanizing practices."

"These tactics (and those of their sister publications MailOnline and the Daily Mail) are not new; in fact, they've been going on for far too long without consequence. For these outlets, it's a game. For me and so many others, it's real life, real relationships, and very real sadness. The damage they have done and continue to do runs deep," she said.

The statement went on: "I share this victory with each of you-because we all deserve justice and truth, and we all deserve better. I particularly want to thank my husband, mom, and legal team, and especially Jenny Afia for her unrelenting support throughout this process."

The Mail on Sunday in response said that it is "carefully considering" the outcome, and may lodge an appeal.

A spokesperson for the newspaper told Insider: "We are very surprised by today's summary judgment and disappointed at being denied the chance to have all the evidence heard and tested in open court at a full trial."

"We are carefully considering the judgment's contents and will decide in due course whether to lodge an appeal," the spokesperson added.