An ex-adviser to the former top public US health official Anthony Fauci has been indicted by Trump administration prosecutors on accusations that he illicitly concealed federal records during the Covid pandemic.

The justice department on Tuesday announced charges against David Morens, 78, of Chester, Maryland, amid a sharply divisive debate over the origins of the coronavirus, which has become particularly politicized during Donald Trump’s two presidencies. Competing theories – including a natural spillover versus a potential lab leak – have fueled partisan clashes, with splits along ideological lines.

Morens served as a senior adviser in the office of the director at the National Institute of Allergy and Infectious Diseases from 2006 to 2022 (Niaid). Fauci had served as director of the Niaid from 1984 to 2022, spearheading the White House’s response to the pandemic during Donald Trump’s first presidency.

In addition to their criticism of Fauci and other scientists for being dismissive of the lab leak theory, Trump and his Republican allies criticized Fauci for urging Americans to take measures to protect themselves from spreading and contracting the potentially deadly virus, including wearing masks and getting vaccinated.

The Trump administration’s justice department alleged two co-conspirators in the indictment against Morens but stopped short of naming them.

An attorney for Morens, Timothy Belevetz, declined a request for comment.

According to the indictment, the Niaid awarded a research grant to a company and an unnamed co-conspirator, who then issued a sub-award to the Wuhan Institute of Virology in China.

The National Institutes of Health (NIH) – under which the Niaid is housed – later terminated the grant, based on allegations that Covid may have emerged from the Wuhan lab.

After the grant’s termination, prosecutors alleged that Morens and others tried to help restore the funding and allegedly “counter the narrative that Covid-19 leaked from a lab”.

Morens and two co-conspirators – anticipating that their communications would be requested under the federal Freedom of Information Act – “agreed in writing to intentionally hide from public view their communications by corresponding using Morens’s personal Gmail account, rather than his official NIH email account”, the justice department alleged in a statement.

Prosecutors alleged the group used Morens’s personal email to share non-public NIH information, coordinate efforts to influence funding decisions, help draft and edit letters aimed at persuading leadership at the institutes, and exchange “back-channel” communications with senior officials.

The justice department also alleged that Morens and one co-conspirator plotted “to pay illegal gratuities”, claiming the individual sent Morens wine for his “behind-the-scene shenanigans” and arranged delivery to his Maryland residence.

The justice department’s statement continued: “Morens then allegedly identified an official act that he could perform to ‘deserve’ the gift, which was a scientific commentary in a prominent medical journal advocating that Covid-19 had natural origins.”

It added that the same co-conspirator allegedly suggested providing Morens “with additional things of value, including meals at Michelin-starred restaurants in Paris, New York and Washington DC”.

In a statement, the US acting attorney general Todd Blanche, who previously served as a personal lawyer for Trump, said: “These allegations represent a profound abuse of trust at a time when the American people needed it most – during the height of a global pandemic.”

Morens faces counts including conspiracy against the US; destruction, alteration, or falsification of records in federal investigations; concealment, removal, or mutilation of records; and aiding and abetting.

If ultimately convicted as charged, Morens could face up to five years in prison for conspiracy, up to 20 years for each count of falsifying records, and up to three years for each count related to concealing or destroying records.