A federal judge in Virginia on Friday sharply questioned special counsel Robert Mueller’s authority to bring tax and bank fraud charges against former Trump campaign chairman Paul Manafort.

“I don’t see what relationship this indictment has with anything the special counsel is authorized to investigate,” said US District Judge T.S. Ellis III of the Eastern District of Virginia.

“You don’t really care about Mr. Manafort,” Ellis told Mueller’s team, suggesting that they lied about the scope of the probe and are seeking “unfettered power” to bring down the president.

“You really care about what information Mr. Manafort can give you to lead you to Mr. Trump and an impeachment — or whatever,” he said, according to Fox News.

The Virginia indictment alleges Manafort hid millions of dollars he earned as an adviser to pro-Russia politicians in Ukraine from the Internal Revenue Service before Donald Trump ran for president.

During the hearing in Alexandria, Manafort’s lawyers fought to dismiss an 18-count indictment — saying the charges go far beyond Mueller’s mandate to probe Russian meddling in the 2016 election and any possible collusion.

The hearing became heated when it was revealed that at least some information derived from an earlier Justice Department probe.

Government lawyers admitted that Manafort had been investigated for years in the Eastern District of Virginia before Mueller was ever appointed as special counsel.

Ellis said it was implausible to think the charges — about Manafort’s business dealings and tax returns from about 2005 through 2015 — could have real ties to Trump’s 2016 presidential campaign.

The judge suggested the real reason Mueller is pursuing Manafort is to pressure him to “sing” against the president, though he also acknowledged that such a strategy is a “time-honored practice” for prosecutors.

Government lawyer Michael Dreeben argued that Mueller’s mandate is broad, and that Manafort fits within that jurisdiction because of his ties to both the Trump campaign and to Ukrainian and Russian officials.

“We needed to understand and explore those relationships and follow the money where it led,” Dreeben said.

Dreeben also said the Justice Department has wide discretion to set its own rules for what should be considered the special counsel’s jurisdiction, and that a judge has no role trying to regulate it.

“We are the Justice Department,” Dreeben said of the special counsel’s office. “We are not separate from the Justice Department.”

But Ellis lashed back.

“I’m sure you’re sensitive to the fact that the American people feel pretty strongly about no one having unfettered power,” he said, asking Dreeben whether the special counsel had already blown through its $10 million budget.

Dreeben declined to answer.

Ellis withheld ruling on the motion and will issue a written decision at a later date.

Manafort also faces charges in Washington, DC, where he is accused of conspiring to launder money and failing to register as a foreign agent when he lobbied for the Ukrainian government.

His lawyers made similar arguments seeking dismissal to the judge in Washington. She has also not yet ruled on the motion.

With Post wires