Judge Andrew Napolitano said Tuesday that a New York federal probe is looking into whether unlawful foreign donations were made to President Trump's inaugural committee. 

Federal prosecutors separate from Special Counsel Robert Mueller's team issued a subpoena for documents Monday.

FoxNews.com reported

The subpoena was first reported by The Wall Street Journal, which revealed that prosecutors had asked for "all documents" related to the committee's donors and vendors, as well as records relating to "benefits" that donors received after making contributions. They also requested documents relating to donations "made by or on behalf of foreign nationals, including but not limited to any communications regarding or relating to the possibility of donations by foreign nationals."

The Journal reported in December that prosecutors were looking into whether the committee misspent the $107 million it raised to stage events celebrating Trump's inauguration in January 2017, as well as whether donors made contributions in exchange for political favors -- a potential violation of federal corruption laws.

The head of the inaugural committee, California real estate investor Tom Barrack, previously told The Associated Press he was questioned by Special Counsel Robert Mueller in 2017. Barrack told the AP he was not a target of the Mueller investigation, which has been looking into Russian interference in the 2016 elections. The Journal reported that Barrack was not mentioned in the subpoena received by the committee Monday.

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Napolitano said he believes the investigation stems from cooperation from Rick Gates, Barrack's deputy on the inaugural committee, in the Mueller probe and Michael Cohen, Trump's former attorney and fixer.

The Fox News senior judicial analyst emphasized that the New York federal prosecutors involved in the matter "enjoy the highest reputation for ethical propriety and professionalism of any prosecutor's office in the country."

"Anybody will tell you that. They are not on a witch hunt or a fishing expedition. They believe there is something here. Whether that leads them to Donald Trump or not remains to be seen," he explained on "Outnumbered Overtime."

He said the inauguration did not cost $100 million, so investigators are focused on the sources for the donations and what became of the funds. 

Watch the full interview above.

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