Judge Jeanine Pirro called special counsel Robert Mueller's investigation "out of control" as the Senate seeks testimony under oath from Donald Trump Jr., Paul Manafort and Jared Kushner.

Trump's oldest son and Manafort, his former campaign manager, are scheduled to testify before the Senate Judiciary Committee on July 26. Committee chairman Charles Grassley (R-IA) said subpoenas will go out if the two do not voluntarily testify.

Kushner, Trump's son-in-law and a top White House adviser, is set to appear behind closed doors with the Senate Intelligence Committee on Monday.

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Discussing the developments with Sandra Smith, Judge Pirro said she thinks Manafort and Trump Jr. will testify, but their lawyers will make the final call. 

"This is a danger zone. Whenever you go in and you say something inconsistent and you're under oath, then it's perjury. It's a perjury trap. Prosecutors do it all the time," said Pirro.

She said Trump's son and son-in-law are "in the crosshairs" of Mueller's probe, which is reportedly expanding to look into the family's finances.

Pirro agreed with Trump's warning to Mueller that looking into financial transactions would be outside the scope of the investigation. 

"This is a fishing expedition. Mueller is like this with Jim Comey. They are pals ... There is an agenda here and the fact that they are going so far beyond the mandate of the special counsel is not a good sign," she concluded. 

Pirro also pointed out the connections to Democrats on the investigative team brought in by Mueller. 

Watch the "America's Newsroom" discussion above and don't miss Judge Pirro on "Justice" on Saturdays at 9:00pm ET on Fox News Channel. 

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