Lady Lawrence became involved in the litigation after receiving a personal email from the Duke of Sussex
Prince Harry has pledged to shield Doreen Lawrence from any financial liability arising from their unsuccessful legal action against the Daily Mail's publisher.
The Duke of Sussex will personally ensure the social justice campaigner bears no costs whatsoever from the defeated lawsuit, according to sources close to the matter.
"Nobody, least of all the duke, who is very protective over Doreen, is going to see her out of pocket," a source familiar with the situation told the Guardian.
Lady Lawrence, whose son Stephen was murdered in 1993, was among seven individuals who brought claims against Associated Newspapers Ltd alleging unlawful information gathering practices.
Mr Justice Nicklin dismissed every allegation brought by the group at the High Court, delivering a comprehensive victory for the Mail titles.
The claimants had accused ANL of bugging, intercepting landline calls, hacking phones and obtaining private information through deception.
Alongside Harry and Lady Lawrence, the case was brought by Sir Elton John and his husband David Furnish, actors Elizabeth Hurley and Sadie Frost, and former Liberal Democrat minister Simon Hughes.
All 55 published stories cited in the proceedings were found not to involve unlawful information gathering, the judge ruled. Three additional alleged incidents that never resulted in articles were similarly rejected.
Associated Newspapers Ltd has confirmed it intends to reclaim its substantial defence costs from the claimants.
Mail sources have suggested the total bill could reach as high as £50million, though individuals close to the proceedings believe the actual recoverable amount may represent only a fraction of that figure, based on earlier court decisions.
Hearings to determine the final costs are scheduled to commence later this month.
The claimants must now also consider whether to mount an appeal against what amounted to a total defeat for their case. The ruling represented a complete vindication for the Mail titles across every allegation.
Lady Lawrence became involved in the litigation after receiving a personal email from Harry alerting her to information that "had come to light" which he believed she would want to know about.
She subsequently met with solicitor Anjlee Sangani and lead barrister David Sherborne at the Corinthia hotel in London, where they informed her that details had "accidentally surfaced" during a conversation between two private investigators.
Insurance policies were arranged to protect the claimants should they lose. The court approved combined budgets totalling approximately £8.5million for both sides, which the insurance would cover.
However, Mr Justice Nicklin retains the power to order payments exceeding these approved amounts.
