Newsom had vowed to release annual tax returns during his 2018 campaign for governor, calling it a “moral duty” in what was viewed as a shot at President Donald Trump, who broke tradition by declining to voluntarily release his returns.

But the wine entrepreneur turned Democratic superstar mysteriously went dark on that front after his 2022 reelection, last releasing details for tax year 2020 more than four years ago.

“The Governor and First Partner publicly disclose their income annually. They have released every tax return that had been filed while he was a candidate for statewide office, covering 2015 through his 2022 re-election,” said Newsom’s spokesperson Tara Gallegos in an email.

“We are working to prepare the remaining returns for transparency. Unlike Donald Trump, the Governor has nothing to hide,” she added.

Newsom’s office didn’t provide a timeline for the tax disclosures.

The governor was asked about the tax returns by Calmatters in 2024, and spokesperson Nathan Click claimed at the time they would eventually be provided to reporters “in a controlled setting.”

“Gavin Newsom’s lack of transparency is unsurprising and deeply hypocritical. After making a big deal of promising to release his tax returns, he has failed to turn over any returns for years,” said Caitlin Sutherland, executive director of Americans for Public Trust.

“This raises significant questions about just what the Newsoms are hiding, especially as they are under federal investigation,” she added.

The Newsoms’ family fortune —which includes a $9 million estate in posh Marin County, another $3.7 million home in Fair Oaks and a sprawling wine empire — has been the subject of scrutiny since sources revealed this week that Siebel Newsom’s taxes are one focus of multiple federal probes surrounding the governor.

The couple earned about $1.5 million in income and paid $480,000 in taxes, according to Newsom’s 2020 tax return.

The pair took out a massive mortgage of $6.5 million to purchase their estate in Kentfield, about 20 minutes north of San Francisco, through an LLC created by Siebel Newsom. No “entities outside of the family” provided financial help, CalMatters reported.

Newsom earns $246,000 in salary as governor while Siebel Newsom has paid herself between $150,000 and $300,000 annually through her gender justice nonprofit, the Representation Project, and a for-profit documentary film company called Girls Club Entertainment.

Newsom’s extensive holdings in the wine and hospitality business include luxury wine shop Plumpjack, wineries and distribution businesses, according to his economic disclosures filed annually. He got his start with the help of billionaire oil heir Gordon Getty and was already worth millions by the time he ran for mayor of San Francisco.

The US Attorney’s Office in the Eastern District of California is specifically probing allegations brought forward by California whistleblowers regarding Siebel Newsom’s taxes, a source said, along with his former chief of staff, Dana Williamson and potentially current staffers.

“There are clearly no boundaries to what Donald Trump will do to get his way or to challenge those who get in his way,” Siebel Newsom said in a statement.

“This is not presidential behavior, and the Governor and I will continue to speak truth to power because the American people deserve so much more,” she said.