Martha MacCallum grilled House Intelligence Committee Democrat Eric Swalwell on several topics, including the Mueller probe and Swalwell's stated promise to investigate several aspects of President Donald Trump.

MacCallum said that Republicans may try to pass a federal budget package before the end of the year -- one that would likely include both relief for Californians affected by wildfires and funding for a Mexican border wall.

Swalwell, who represents Alameda and Contra Costa Counties in the Golden State, said that "ideally we can have border security -- maybe not a physical wall -- and take care of people in California."

MacCallum pressed Swalwell on his claim that he wants the incoming House Democratic majority to focus on legislating and not "chasing every ball" when it comes to investigating Trump.

She cited a recent tweet of his, which said that "the days are presidential immunity are over... No more free passes to cash in on access to the Oval Office. No more colluding with Russia, and we'll see if you're a tax cheat."

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MacCallum said that the tweet did not back up his other assertion.

Swalwell said that there are many other "balls" to chase and that the items listed are only a few of the things he would like to see probed.

"We're going to insist that we protect the rule of law in our country and the Mueller investigation," he said.

MacCallum also asked Swalwell to defend another statement he made, saying that new acting attorney general Matt Whitaker was hired as an "assassin to kill the Russia investigation."

"What evidence do you have of that?" she asked.

Watch more above.

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