Hunter Biden sued Rudy Giuliani and his former attorney Tuesday, claiming they hacked and manipulated data on an external hard drive associated with his laptop.

Giuliani and the attorney, Robert Costello, have frequently acknowledged accessing the hard drive's data. The lawsuit accuses them of having "dedicated an extraordinary amount of time and energy toward looking for, hacking into, tampering with, manipulating, copying, disseminating, and generally obsessing over data that they were given that was taken or stolen."

Giuliani has sought to paint Hunter Biden as a corrupt businessman, who cashed in on his father's political power. He and Costello have said they were provided the hard drive in 2020 by a Delaware computer repair shop owner who claims Hunter Biden dropped off the laptop the year before and never returned to retrieve it. In May, Hunter Biden also sued the computer repair shop owner, John Paul Mac Isaac, who has denied wrongdoing and said he obtained the laptop legally.

The lawsuit against Giuliani and Costello claims they used Hunter Biden's username to gain access to his data, making copies and sharing it with allies such as Steve Bannon. 

Costello declined to comment. Giuliani's spokesperson and political advisor, Ted Goodman said, "Hunter Biden has previously refused to admit ownership of the laptop."

"I'm not surprised he's now falsely claiming his laptop hard drive was manipulated by Mayor Giuliani, considering the sordid material and potential evidence of crimes on that thing," Goodman said.

The data led to a steady trickle of revelations about Hunter Biden's often tortured personal life, and jetsetting professional life. Emails and images purportedly from Hunter Biden's laptop data have fueled countless headlines in conservative media and Republican claims of corruption. 

But the lawsuit claims some of the data was "tampered with, manipulated" and "altered."

The lawsuit cites statements Giuliani made on a podcast and his nightly YouTube show, in which he boasted about his access to the data. 

"This belongs to Hunter Biden," Giuliani said, while holding up a laptop during a Feb. 2, 2023 episode of "America's Mayor Live."

"He proceeded to brag about having copied [Hunter Biden's] data onto his own computer and about having accessed, analyzed and manipulated the transferred data," according to the lawsuit.

Last year, Brian Della Rocca, a lawyer for Mac Isaac, provided to CBS News what he called an "exact copy" of laptop data given by his client to federal investigators in 2019. 

An independent analysis, by two cyber investigators from Minneapolis-based Computer Forensics Services, found no evidence that the user data had been modified, fabricated or tampered with. But some versions of the hard drive circulated later appeared to have had data added after April 2019, a sign they could have been tampered with, according to reports in other media outlets, including The Washington Post.

The lawsuit is the latest move in a monthslong effort by Hunter Biden's legal team to aggressively push back against his Republican antagonizers. In February, his attorney, Abbe Lowell, sent letters to 14 prominent Republican media personalities and former officials who had accused Hunter Biden of corruption or disseminated material purporting to be from the laptop. Lowell's letter served "notice that a litigation hold should be in effect for the preservation and retention" of their records related to Hunter Biden.

They've since sued Mac Isaac, the IRS, a former Trump White House aide, and sent a cease and desist letter to former President Donald Trump's legal team, alleging defamation.

The lawsuit against Giuliani comes amid mounting legal troubles for both Giuliani and Hunter Biden. Giuliani was indicted by a Fulton County, Georgia grand jury on Aug. 15, along with former President Donald Trump and 17 others, and accused of taking part in a "criminal enterprise" while trying to overturn the state's 2020 presidential election results.

A month later, Hunter Biden was indicted by a federal grand jury on charges related to his alleged purchase of a firearm in October 2018 while he was allegedly a drug user. The indictment came after a plea deal fell apart in July between the government and Hunter Biden's attorneys regarding his taxes and a diversion agreement on a firearms charge.

Giuliani and Hunter Biden have each entered not guilty pleas in their respective cases, and deny wrongdoing.

Giuliani and Costello had for nearly half a century been close friends, a bond that appeared to fracture suddenly, when Costello sued Giuliani on Sept. 19. Costello, who has represented Giuliani in a variety of criminal and civil matters, claimed in the suit that Giuliani owes his law firm nearly $1.4 million in unpaid legal fees.

Giuliani told CBS News he was "personally hurt" by Costello's lawsuit. Costello shot back, saying Giuliani had taken "the low road."

In:
• Rudy Giuliani
• Hunter Biden

Graham Kates

Graham Kates is an investigative reporter covering criminal justice, privacy issues and information security for CBS News Digital. Contact Graham at [email protected] or [email protected]