(Bloomberg) -- Alphabet Inc.’s Google told a federal court Thursday that it should be allowed to interview the Justice Department’s top antitrust official under oath, alleging his “deep-seated bias” against the company led the federal government to sue it for antitrust violations.

Before becoming assistant attorney general for antitrust in November 2021, Jonathan Kanter represented a number of ad tech companies and Google rivals, the search giant said. That included Magnite Inc., OpenX Ltd., Roku Inc., News Corp., and the News Media Alliance, a trade association representing more than 2,000 news publishers including the New York Times, Gannett Co., Axel Springer SE and others. Google alleged that those companies paid Kanter millions of dollars to advocate for bringing antitrust cases against it.

Kanter’s alleged bias “shaped and infected this entire proceeding, and reflects an improper predisposition to find against Google, rather than ensure that justice is done,” the company said in a court document Thursday.

Kanter is now recused from the case after Google hired his former law firm, Paul Weiss Rifkind Wharton & Garrison LLP to represent it in April.

The Google filing is the latest bid to discredit the Biden administration’s top antitrust officials – Kanter and FTC Chair Lina Khan – on ethics grounds amid a push by the federal agencies to stem the market power of the largest US tech giants. Meta Platforms Inc. and Amazon.com Inc. have also unsuccessfully sought to bounce Khan from participating in antitrust cases involving them on ethics grounds.

The Justice Department and a group of state attorneys general sued Google in January for allegedly monopolizing the market for online advertising technology. The agency separately filed another antitrust suit against the search giant in 2020 for monopolization of online search. That case is set to go to trial next month.

This month, the Justice Department asked US District Judge Leonie Brinkema to bar Google from arguing that the antitrust case represents “improper selective enforcement” of the law. In an Aug. 18 filing, the agency said that Google has sought unfounded discovery related to Kanter, even though he is currently recused from the case.

“There is no basis in law or fact to suggest that this enforcement action is the result of anything other than a considered and deliberate investigation,” the Justice Department said, noting that the investigation began during the prior administration and 17 states are also prosecuting the case.

Kanter joined Biden’s Justice Department after a long career focused on the intersection of antitrust and digital platforms. While in private practice, he represented a number of critics of Google and Apple Inc., who pushed for greater enforcement of the antitrust laws.

Kanter was barred from participating in the Google case for his first year, the Justice Department said, during which time his top deputy, Doha Mekki, was in charge of the probe. Kanter was cleared to work on the case after a one-year cooling off period expired in November 2022, the agency said. 

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