Pirro began the discussion by defending the commander-in-chief.
According to the anchor, Trump did nothing wrong, and the transcript of his conversation with Ukrainian President Volodymyr Zelensky does not suggest that he should be impeached.
Trump is being accused of using the power of his office to pressure the Ukrainian government to investigate one of his main political rivals, former Vice President Joe Biden.
But, according to Pirro, the U.S. and the eastern European country have a treaty according to which American authorities are allowed to discuss such investigations with Ukrainian officials.
"We have a treaty with Ukraine where we have the right to have our Attorney General Bill Barr discuss with them any information or evidence that involves criminal activity," the host said.
Echoing Trump, Scalise said that "there was no quid pro quo" agreement between the president and the Ukrainian government.
According to the top Republican, Trump was simply "carrying out his duty," and helping Ukraine get rid of corruption.
The lawmaker argued that Zelensky ran on an anti-corruption platform, which is why alleged corruption pertaining to the Bidens was the main subject of his conversation with Trump.
"Zelensky even thanked President Trump for selling them the javelin missiles that allows them to stand up to Russia," Scalise said.
However, seemingly not satisfied with the answer, Pirro suggested that Republicans in Congress are not doing enough to defend the president.
"With all due respect congressman," Pirro said, "You guys don't fight the way the Democrats fight."
The host told Scalise that it is "frustrating" to watch Republicans not fighting hard enough for Trump, arguing that they should have been more aggressive toward former President Barack Obama.
"You had the goods -- when Obama isn't selling what he agreed to sell and Russia and he's defending Russia when they are taking out the defense system over the Ukraine," Pirro said.As Mediaite notes, Obama was criticized for not providing missile weapons to Ukraine, even though his administration supplied the country with over $600 million in military equipment.
Although Obama faced criticism for not being sufficiently aggressive toward Russia, and for not arming Ukraine, he was never accused of having a quid pro quo agreement with the country's authorities.
According to House Democrats, Trump had such an agreement with the Ukrainian government. The president, they claim, threatened to cut military aid unless Biden is investigated, and did so in order to damage the former vice president's White House bid.
Trump has denied any wrongdoing, insisting that his conversations with Zelensky were "perfect."