Attorney General Jeff Sessions is set to testify before the Senate Intelligence Committee Tuesday afternoon as part of the ongoing Russia probe.

Lawmakers – particularly Democrats – are preparing tough questions for Sessions both about Russia’s contact with Trump campaign associates and the circumstances of former FBI Director James Comey’s firing.

Judge Andrew Napolitano joined Steve Doocy this morning to share insight on what peril Sessions might be facing at today's open hearing.

Napolitano said Sessions has three main interests to defend, the first of which is his own integrity.

He explained that Democrats are going to accuse Sessions of perjury for not properly disclosing his meetings with Russian officials during the 2016 campaign.

"There's enough there for them to stir the pot on this," Napolitano said. "I don't know if he lied. I don't know if he intentionally lied. But all the information about his contacts with the Russian ambassador - which I think were either routine or harmless - nevertheless, were not articulated truthfully at the time that they should have been."

A second issue is that Sessions will want to challenge some of the testimony of Comey, who really went after President Trump during his dramatic hearing with Congress last week, Naplolitano said.

During his hearing, Comey testified that Trump asked him for his loyalty and asked him to end the probe into former national security adviser Michael Flynn, allegations the president strongly pushed back on.

Napolitano said the third issue - and perhaps the "stickiest" - is that Sessions is still the attorney general and he is there to defend the integrity of Justice Department investigations, including special counsel Robert Mueller's independent Russia probe. He noted that Sessions, however, can have no involvement in that investigation, since he's already recused himself.

"Bottom line: This is a moment unique in history," Napolitano said. "He is there not as the person monitoring these investigations - some intelligence, some law enforcement - but as a witness in two of them."

Watch more above, and tune in to Fox News Channel's coverage of Sessions' hearing, starting at 2:30 p.m. ET.

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