Former FBI director and now special counsel Robert Mueller is investigating alleged influence by Russia on the 2016 presidential election, and he reportedly has expanded the scope to the business interests of associates of President Trump, but has yet to present evidence of any crime.

Now, he's declining to release details of his spending on the probe, prompting Washington watchdog Judicial Watch to file a Freedom of Information Act lawsuit against the Department of Justice.

Last summer, Mueller submitted a proposed budget to the DOJ, but Judicial Watch said officials declined to make the document public and committed only to releasing reports of the team's expenditures every six months.

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It's just one of multiple cases Judicial Watch is pursuing over Mueller's investigation. Other cases focus on the surveillance, unmasking and illegal leaking targeting President Trump and his associates during the FBI's investigation of potential Russian involvement in the 2016 presidential election.

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Mueller later took over that investigation.

"The Mueller special counsel investigation is growing with seemingly little concern about costs to the taxpayer," said Judicial Watch President Tom Fitton. "Is the Justice Department hiding basic budget information about the Mueller special counsel operation because taxpayers and Congress would be outraged by the costs?

Fitton argued Mueller "is not above the law and he shouldn't be able to keep his budget secret."

"No one else in D.C. seems to be providing oversight of the Mueller juggernaut, so once again it is up to the citizens group Judicial Watch to go to court and demand accountability," he said.

The lawsuit seeks copies of the budget proposed by Mueller, communications about those expenditures and copies of documents that might govern Mueller's appointment.

WND reported last month some critics argue an investigation into collusion with Russia during the 2016 race should not exclude Democratic presidential nominee Hillary Clinton.

As secretary of state, Clinton approved a deal to sell Uranium One, a company that controlled a fifth of U.S. uranium production, to the Russian atomic agency Rosatom. As reported by the New York Times, nine investors in the deal then funneled $145 million to the Clinton Foundation.

Later, her husband received, among other things, a $500,000 speaker fee from a Moscow-based investment bank while Clinton was secretary of state.

Rep. Dana Rohrabacher, R-Calif., said there should be a special prosecutor to look into those documented transactions.

The significant donations Russian financiers made to the Clinton Foundation should not be overlooked, Rohrabacher said in a letter to House Foreign Affairs Committee Chairman Ed Royce.

"These hearing should take a close look at possible involvement Hillary Clinton may have had with Russian financiers who donated heavily to the Clinton Foundation. There is ample evidence to justify an under-oath examination of the relationship between the donations and the 2013 CFIUS approval of the sale of America's uranium reserves," Rohrabacher wrote.

Rohrabacher, who chairs the House Foreign Affairs Subcommittee on Europe, Eurasia and Emerging Threats, claimed to have obtained "new evidence" the Obama administration was aware of Clinton's involvement in the Uranium One scandal.

"This request is prompted by new evidence that the Obama administration had prior knowledge of possible bribery and violations of the Foreign Corrupt Practices Act involving state-owned Russian nuclear industry figures, the Clinton Foundation, and Americans prior to the CFIUS approval of the uranium transaction," the letter stated.

At the same time, WND reported a former Justice Department prosecutor has filed an ethics complaint with the DOJ's Office of Professional Responsibility seeking the removal and prosecution of Mueller over leaks resulting from his grand jury investigation into allegations Russia colluded with the Trump campaign in 2016.

Larry Klayman, the founder of Freedom Watch, explained in his complaint that the Justice Department's Office of Professional Responsibility and the inspector general are "charged with investigating and remedying unethical and illegal behavior by the special counsel and other DOJ lawyers and staff."

"Special Counsel Mueller derives his office and powers from the DOJ, as he was appointed, strangely, by Deputy Attorney General Rod Rosenstein."

Klayman charged Attorney General Jeff Sessions and Rosenstein have "failed and apparently refuse to properly police the illegal grand jury leaks and conflicts of interest of Special Counsel Mueller – putting their own personal, political and professional interests before all else – the job falls upon Freedom Watch and OPR and the IG to represent the interests of the American people for truth and justice."

"If OPR and the IG themselves fail to take action, Freedom Watch will file a court complaint to force them to take appropriate action," Klayman said.

It also was reported in August that Mueller was impaneling a grand jury to continue his investigation.

Twelve attorneys from the Justice Department and FBI are working with the special counsel's office, and three are from Mueller's firm, WilmerHale. At least eight members of Mueller's team have associations with the Democratic Party or have a track record of making donations to Democratic candidates, including the presidential campaigns of Obama and Clinton.

Mueller's judgment has been under question since he was picked.

Judicial Watch earlier pointed out Mueller was the FBI director who "caved" to the demands of radical Islamic groups and removed critical training materials from the government's library of available resources.

He had no sooner been appointed to investigate Russia collusion and "related matters" when he faced a call for his resignation.

Gregg Jarrett in a commentary at Fox News said that since Mueller worked closely with now-fired FBI chief James Comey, there's a clear conflict of interest.

"The problem arises in his duty to fairly and objectively evaluate the evidence he gathers," Jarrett wrote. "How can Americans have confidence in the results if they know the special counsel may harbor a conspicuous bias. They cannot."

He said: "So what exactly is Mueller's conflict? He and James Comey are good friends and former colleagues who worked hand-in-hand for years at the FBI. Agents will tell you they were joined at the hip. They stood together in solidarity, both threatening to resign over the warrantless wiretapping fiasco involving then-Attorney General John Ashcroft in 2004."

This, Jarrett wrote, "is precisely the kind of association which ethical rules are designed to guard against."

He said Mueller clearly will "morph" his investigation of Russia into a review of a meeting between President Trump and Comey in which the president allegedly asked Comey to end the investigation of former National Security Adviser Michael Flynn.

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