In a decision posted Friday, US District Judge Paul Oetken said he agrees a “special master” is necessary to “ensure the “perception of fairness” in the investigation into Giuliani.
The judge had ordered both the prosecutors and defense team to submit a list of candidates to serve in that role by June 4.
He has not been charged and has denied wrongdoing.
Prosecutors are looking into whether Giuliani violated foreign lobbying laws by operating on behalf of Ukrainian officials when he sought the ouster of the then-US ambassador to Ukraine, Marie Yovanovitch, while urging Ukraine to investigate Trump’s 2020 political rival, then-Democratic presidential candidate Joe Biden, and his son Hunter. US law requires anyone lobbying on behalf of a foreign government or official to register and failing to do so is a violation.
Giuliani has claimed his activities in Ukraine were done in his capacity as a lawyer for Trump, and that he “never represented a Ukrainian national or official before the United States government.”
On April 28, federal agents executed search warrants at Giuliani’s Manhattan apartment and Park Avenue office, seizing 18 electronic devices, according to prior court filings. Prosecutors also disclosed that they had covertly searched Giuliani’s iCloud account in 2019.
Giuliani argued the searches were problematic given his status as a lawyer and that the materials seized in the April raid should be returned to him so he could review them for “responsiveness and privilege.”
Denying Giuliani’s request, Oetken on Friday wrote that lawyers are “not immune” from searches in criminal investigations and the searches in this case “were based on probable cause.”
The judge declined Giuliani’s request to see the results of the 2019 iCloud search, saying that the government’s use of a separate team of attorneys and agents to filter through the content was adequate to protect attorney-client privileges.
Oetken also turned down another request from Giuliani for the affidavits submitted in support of the 2019 and 2021 warrants to be unsealed so he can challenge the legality, saying Giuliani is not entitled to a preview of the government’s evidence before he has been charged.
As part of the same investigation, agents on April 28 also executed a search warrant at the home of Victoria Toensing, a lawyer and Giuliani ally. The special master will also review those materials taken from Toensing.
This story has been updated.
CNN’s Erica Orden contributed to this report.