The US Department of Justice is making a novel legal argument to keep a recording of an interview with Joe Biden from becoming public. In a filing late last week, the bureau cited the risk of AI-generated deepfakes as one of the reasons it refuses to release audio of the president’s interview with special counsel Robert Hur. The conversation about Biden’s handling of classified documents is a source of heated political contention, with Republicans pushing for release of the recordings and the White House moving to block them.

The justice department’s filing, which it released late on Friday night, argues that the recording should not be released on a variety of grounds including privacy interests and executive privilege. One section of the filing, however, is specifically dedicated to the threat of deepfakes and disinformation, stating that there is substantial risk people could maliciously manipulate the audio if it were to be made public.

“The passage of time and advancements in audio, artificial intelligence, and ‘deep fake’ technologies only amplify concerns about malicious manipulation of audio files,” the justice department stated. “If the audio recording is released here, it is easy to foresee that it could be improperly altered, and that the altered file could be passed off as an authentic recording and widely distributed.”

The filing presents a novel argument about the threat of AI-generated disinformation from the release of government materials, potentially setting up future legal battles over the balance between transparency and preventing the spread of misinformation.

“A malicious actor could slow down the speed of the recording or insert words that President Biden did not say or delete words that he did say,” the filing argues. “That problem is exacerbated by the fact that there is now widely available technology that can be used to create entirely different audio ‘deepfakes’ based on a recording.”

Biden’s interview with Hur reignited a longstanding conservative campaign of questioning Biden’s mental faculties and drawing attention to his age, which critics claim make him unfit to be president. While Hur’s report into classified documents found at Biden’s private residence did not result in charges against him, the special counsel’s description of him as an “elderly man with poor memory” became ammunition for Republicans and prompted Biden to defend his mental fitness.

Although transcripts of Hur’s interview with Biden are public, conservative groups and House Republicans have taken legal action, filed Freedom of Information Act requests and demanded the release of recorded audio from the conversation as he campaigns against Donald Trump. Biden has asserted executive privilege to prevent the release of the audio, while the latest justice department filing pushes back against many of the conservative claims about the recording.

The justice department’s filing argues that releasing the recording would create increased public awareness that audio of the interview is circulating, making it more believable when people encounter doctored versions of it.

A number of politicians have become the target of deepfakes created in attempts to swing political opinion, including Biden. A robocall earlier this year that mimicked Biden’s voice and told people not to vote in New Hampshire’s Democratic primary was sent to thousands of people. The political consultant allegedly behind the disinformation campaign is now facing criminal charges and a potential $6m fine.