Watch: GOP senator flails as Fox's Maria Bartiromo presses him for Biden evidence

Sen. Ron Johnson (R-WI) was asked by Fox Business's Maria Bartiromo to provide proof that President Joe Biden had benefited from his son's overseas business dealings — and came up woefully short in his response.

While discussing the GOP's impeachment inquiry into Biden, Bartiromo asked Johnson to point to specific proof of wrongdoing by the president that would justify removing him from office.

"Well, first of all, he's lied repeatedly," said Johnson. "Why do you lie repeatedly if you don't have something to cover up? President Biden is the don of the Biden crime family. Oftentimes the dons kind of sit above all the criminal activity that occurs, but they're totally responsible for it."

This did not leave Bartiromo satisfied, however.

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"But the evidence that actually proves that is what I'm asking for," she said. "Did Joe Biden benefit from all of this?"

Johnson went on to say, "It depends on what documents [investigators] have, the Bidens have not exactly been forthcoming in cooperating with the investigations here."

Johnson concluded by saying that Biden and his family "can't cover up their guilt."

The impeachment inquiry was dealt a massive blow earlier this month when one of its star witnesses, longtime FBI informant Alexander Smirnov, was charged with lying to investigators about alleged multimillion-dollar bribes that President Joe Biden supposedly received from Ukrainian energy firm Burisma.

While the Republican inquiry has turned up some unseemly details about Hunter Biden's professional and personal lives, it has yet to find a direct link between his business dealings and his father.

The House impeachment inquiry into President Joe Biden has been criticized for its lack of evidence for the GOP's allegations that the president laundered bribes through his son Hunter's international business deals.

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