California's Gavin Newsom alleges justice department is investigating his wife and ex-staff

California Governor Gavin Newsom alleged on Monday that the US Department of Justice is investigating people in his orbit due to his political opposition to President Donald Trump.

"In recent days, federal agents have knocked on the door of family, friends, and former employees," Newsom said in a video. "Not because they found crime, because they're simply trying to find one."

Newsom, a Democrat, acknowledged speculation that he would seek the White House in 2028, alleging Trump was "coming after me because I'm considering running for president."

A source familiar with the investigation confirmed there were "several investigations ongoing" for "roughly a year", but denied Trump's involvement.

The investigations "all originated out of California, working through whistleblowers and government sources," the individual said, requesting anonymity to discuss an ongoing case.

Federal prosecutors in the state capital of Sacramento were handling the investigations, one of which pertained to Newsom's wife's taxes, and another related to Newsom's former chief of staff, the individual said.

The source did not specify which chief of staff, and Newsom did not say which current or former aides were under scrutiny.

But the governor's former chief of staff and a longtime California political operative, Dana Williamson, pleaded guilty to federal charges in May over a campaign finance fraud scheme that did not implicate Newsom.

In his video, Newsom alleged federal investigators were "demanding records" and "abusing the grand jury process."

The current governor of California has grown his national profile by positioning himself as a foil to Trump. Newsom's press team has taken to mocking Trump's caps lock-heavy posting style on social media, and the governor successfully launched a bid to redraw California's congressional districts after Trump urged several Republican-led states to revise their maps ahead of the midterm elections later this year.

Political commentators have long speculated Newsom will use his elevated platform to seek the presidency in the 2028 election.

Newsom portrayed the investigation as an act of political persecution spurred by a potential presidential campaign, and accused the president of corruption. He also alleged that the investigation into his wife, Jennifer Siebel Newsom, was intended to harm him.

"One by one anyone who has challenged Donald Trump has ended up on his hit list, and today, I proudly joined that list," Newsom said.

"Donald Trump picked the wrong target," Newsom said. "We have nothing to hide."

Over the last two years, the justice department has opened prosecutions or investigations of prominent Trump critics or political adversaries.

Federal prosecutors have twice brought charges against former FBI Director James Comey; a judge threw out the first case after finding the prosecutor leading the case was improperly appointed, and the second is ongoing. Comey has denied wrongdoing.

The justice department also unsuccessfully sought to prosecute New York Attorney General Letitia James, who took Trump and his businesses to court over fraud accusations.

Former Federal Reserve Chairman Jerome Powell faced a justice department probe into alleged financial mismanagement of the agency's building renovations as he and Trump clashed over interests rates. The top federal prosecutor in DC later dropped the inquiry, after it threatened to derail US Senate approval of Trump's nominee to replace Powell.

The White House and the justice department declined to comment.

Williamson, Newsom's former chief of staff, pleaded guilty to counts of conspiracy to commit bank fraud and wire fraud, subscribing to a false tax return, and making false statements.

Federal prosecutors had alleged that she participated in a fraudulent scheme to steal campaign funds from an account for a different politician, Xavier Becerra, to personally benefit one of his aides.

Neither Newsom nor Becerra, who is now running governor of California, were implicated in the case.

Prosecutors also accused Williamson of using her position as Newsom's chief of staff to pressure state attorneys to settle a sexual harassment lawsuit against a gaming company that was once her client, the Sacramento Bee reported.

In response to a BBC inquiry, Newsom's office said in a fact sheet that Williamson's conduct was "entirely unrelated to him".

Cai Pigliucci contributed to this report.